/*
  Copyright (c) 2002, 2012, Oracle and/or its affiliates. All rights reserved.

  The MySQL Connector/J is licensed under the terms of the GPLv2
  <http://www.gnu.org/licenses/old-licenses/gpl-2.0.html>, like most MySQL Connectors.
  There are special exceptions to the terms and conditions of the GPLv2 as it is applied to
  this software, see the FLOSS License Exception
  <http://www.mysql.com/about/legal/licensing/foss-exception.html>.

  This program is free software; you can redistribute it and/or modify it under the terms
  of the GNU General Public License as published by the Free Software Foundation; version 2
  of the License.

  This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY;
  without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
  See the GNU General Public License for more details.

  You should have received a copy of the GNU General Public License along with this
  program; if not, write to the Free Software Foundation, Inc., 51 Franklin St, Fifth
  Floor, Boston, MA 02110-1301  USA
 
 */
package com.mysql.jdbc;

import java.io.IOException;
import java.io.UnsupportedEncodingException;
import java.lang.reflect.Array;
import java.lang.reflect.Constructor;
import java.lang.reflect.Method;
import java.nio.ByteBuffer;
import java.nio.CharBuffer;
import java.nio.charset.Charset;
import java.nio.charset.CharsetEncoder;
import java.sql.Blob;
import java.sql.DatabaseMetaData;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.SQLWarning;
import java.sql.Savepoint;
import java.util.ArrayList;
import java.util.Calendar;
import java.util.Collections;
import java.util.Enumeration;
import java.util.GregorianCalendar;
import java.util.HashMap;
import java.util.Iterator;
import java.util.List;
import java.util.Locale;
import java.util.Map;
import java.util.Properties;
import java.util.Random;
import java.util.Stack;
import java.util.TimeZone;
import java.util.Timer;
import java.util.TreeMap;

import com.mysql.jdbc.log.Log;
import com.mysql.jdbc.log.LogFactory;
import com.mysql.jdbc.log.NullLogger;
import com.mysql.jdbc.profiler.ProfilerEvent;
import com.mysql.jdbc.profiler.ProfilerEventHandler;
import com.mysql.jdbc.util.LRUCache;

/**
 * A Connection represents a session with a specific database. Within the
 * context of a Connection, SQL statements are executed and results are
 * returned.
 * <P>
 * A Connection's database is able to provide information describing its tables,
 * its supported SQL grammar, its stored procedures, the capabilities of this
 * connection, etc. This information is obtained with the getMetaData method.
 * </p>
 * 
 * @author Mark Matthews
 * @version $Id$
 * @see java.sql.Connection
 */
public class ConnectionImpl extends ConnectionPropertiesImpl implements
		MySQLConnection {
	private static final String JDBC_LOCAL_CHARACTER_SET_RESULTS = "jdbc.local.character_set_results";

   public String getHost() {
      return host;
   }

   private MySQLConnection proxy = null;
   
   public boolean isProxySet(){
	   return this.proxy != null;
   }

   public void setProxy(MySQLConnection proxy) {
      this.proxy = proxy;
   }

   // We have to proxy ourselves when we're load balanced so that
   // statements get routed to the right physical connection
   // (when load balanced, we're a "logical" connection)
   private MySQLConnection getProxy() {
      return (proxy != null) ? proxy : (MySQLConnection) this;
   }
   
   public MySQLConnection getLoadBalanceSafeProxy() {
	   return this.getProxy();
   }
   

	class ExceptionInterceptorChain implements ExceptionInterceptor {
		List<Extension> interceptors;
		
		ExceptionInterceptorChain(String interceptorClasses) throws SQLException {
			interceptors = Util.loadExtensions(ConnectionImpl.this, props, interceptorClasses, "Connection.BadExceptionInterceptor",  this);
		}
		
		public SQLException interceptException(SQLException sqlEx, Connection conn) {
			if (interceptors != null) {
				Iterator<Extension> iter = interceptors.iterator();
				
				while (iter.hasNext()) {
					sqlEx = ((ExceptionInterceptor)iter.next()).interceptException(sqlEx, ConnectionImpl.this);
				}
			}
			
			return sqlEx;
		}

		public void destroy() {
			if (interceptors != null) {
				Iterator<Extension> iter = interceptors.iterator();
				
				while (iter.hasNext()) {
					((ExceptionInterceptor)iter.next()).destroy();
				}
			}
			
		}

		public void init(Connection conn, Properties properties) throws SQLException {
			if (interceptors != null) {
				Iterator<Extension> iter = interceptors.iterator();
				
				while (iter.hasNext()) {
					((ExceptionInterceptor)iter.next()).init(conn, properties);
				}
			}
		}
	}
	
	/**
	 * Used as a key for caching callable statements which (may) depend on
	 * current catalog...In 5.0.x, they don't (currently), but stored procedure
	 * names soon will, so current catalog is a (hidden) component of the name.
	 */
	static class CompoundCacheKey {
		String componentOne;

		String componentTwo;

		int hashCode;

		CompoundCacheKey(String partOne, String partTwo) {
			this.componentOne = partOne;
			this.componentTwo = partTwo;

			// Handle first component (in most cases, currentCatalog)
			// being NULL....
			this.hashCode = (((this.componentOne != null) ? this.componentOne
					: "") + this.componentTwo).hashCode();
		}

		/*
		 * (non-Javadoc)
		 * 
		 * @see java.lang.Object#equals(java.lang.Object)
		 */
		public boolean equals(Object obj) {
			if (obj instanceof CompoundCacheKey) {
				CompoundCacheKey another = (CompoundCacheKey) obj;

				boolean firstPartEqual = false;

				if (this.componentOne == null) {
					firstPartEqual = (another.componentOne == null);
				} else {
					firstPartEqual = this.componentOne
							.equals(another.componentOne);
				}

				return (firstPartEqual && this.componentTwo
						.equals(another.componentTwo));
			}

			return false;
		}

		/*
		 * (non-Javadoc)
		 * 
		 * @see java.lang.Object#hashCode()
		 */
		public int hashCode() {
			return this.hashCode;
		}
	}

	/**
	 * Marker for character set converter not being available (not written,
	 * multibyte, etc) Used to prevent multiple instantiation requests.
	 */
	private static final Object CHARSET_CONVERTER_NOT_AVAILABLE_MARKER = new Object();

	/**
	 * The mapping between MySQL charset names and Java charset names.
	 * Initialized by loadCharacterSetMapping()
	 */
	public static Map<?, ?> charsetMap;

	/** Default logger class name */
	protected static final String DEFAULT_LOGGER_CLASS = "com.mysql.jdbc.log.StandardLogger";

	private final static int HISTOGRAM_BUCKETS = 20;

	/** Logger instance name */
	private static final String LOGGER_INSTANCE_NAME = "MySQL";

	/**
	 * Map mysql transaction isolation level name to
	 * java.sql.Connection.TRANSACTION_XXX
	 */
	private static Map<String, Integer> mapTransIsolationNameToValue = null;

	/** Null logger shared by all connections at startup */
	private static final Log NULL_LOGGER = new NullLogger(LOGGER_INSTANCE_NAME);

	private static Map<?, ?> roundRobinStatsMap;

	private static final Map<String, Map<Long, String>> serverCollationByUrl = new HashMap<String, Map<Long,String>>();

	/**
	 * Map for Java charsets of user defined charsets. We can't map them statically, because
	 * they can be different for different server URLs.
	 */
	private static final Map<String, Map<Integer, String>> serverJavaCharsetByUrl = new HashMap<String, Map<Integer,String>>();
	/**
	 * Map for user defined charsets. We can't map them statically, because
	 * they can be different for different server URLs.
	 */
	private static final Map<String, Map<Integer, String>> serverCustomCharsetByUrl = new HashMap<String, Map<Integer,String>>();
	/**
	 * Map for user defined charsets. We can't map them statically, because
	 * they can be different for different server URLs.
	 */
	private static final Map<String, Map<String, Integer>> serverCustomMblenByUrl = new HashMap<String, Map<String, Integer>>();
	
	private static final Map<String, Map<String, String>> serverConfigByUrl = new HashMap<String, Map<String,String>>();

	private long queryTimeCount;
	private double queryTimeSum;
	private double queryTimeSumSquares;
	private double queryTimeMean;
	
	private transient Timer cancelTimer;
	
	private List<Extension> connectionLifecycleInterceptors;
	
	private static final Constructor<?> JDBC_4_CONNECTION_CTOR;
	
	private static final int DEFAULT_RESULT_SET_TYPE = ResultSet.TYPE_FORWARD_ONLY;
	
	private static final int DEFAULT_RESULT_SET_CONCURRENCY = ResultSet.CONCUR_READ_ONLY;
	
	static {
		mapTransIsolationNameToValue = new HashMap<String, Integer>(8);
		mapTransIsolationNameToValue.put("READ-UNCOMMITED", TRANSACTION_READ_UNCOMMITTED);
		mapTransIsolationNameToValue.put("READ-UNCOMMITTED", TRANSACTION_READ_UNCOMMITTED);
		mapTransIsolationNameToValue.put("READ-COMMITTED", TRANSACTION_READ_COMMITTED);
		mapTransIsolationNameToValue.put("REPEATABLE-READ", TRANSACTION_REPEATABLE_READ);
		mapTransIsolationNameToValue.put("SERIALIZABLE", TRANSACTION_SERIALIZABLE);

		if (Util.isJdbc4()) {
			try {
				JDBC_4_CONNECTION_CTOR = Class.forName(
						"com.mysql.jdbc.JDBC4Connection").getConstructor(
						new Class[] { String.class, Integer.TYPE,
								Properties.class, String.class, String.class });
			} catch (SecurityException e) {
				throw new RuntimeException(e);
			} catch (NoSuchMethodException e) {
				throw new RuntimeException(e);
			} catch (ClassNotFoundException e) {
				throw new RuntimeException(e);
			}
		} else {
			JDBC_4_CONNECTION_CTOR = null;
		}
	}

	protected static SQLException appendMessageToException(SQLException sqlEx,
			String messageToAppend, ExceptionInterceptor interceptor) {
		String origMessage = sqlEx.getMessage();
		String sqlState = sqlEx.getSQLState();
		int vendorErrorCode = sqlEx.getErrorCode();

		StringBuffer messageBuf = new StringBuffer(origMessage.length()
				+ messageToAppend.length());
		messageBuf.append(origMessage);
		messageBuf.append(messageToAppend);

		SQLException sqlExceptionWithNewMessage = SQLError.createSQLException(messageBuf
				.toString(), sqlState, vendorErrorCode, interceptor);

		//
		// Try and maintain the original stack trace,
		// only works on JDK-1.4 and newer
		//

		try {
			// Have to do this with reflection, otherwise older JVMs croak
			Method getStackTraceMethod = null;
			Method setStackTraceMethod = null;
			Object theStackTraceAsObject = null;

			Class<?> stackTraceElementClass = Class.forName("java.lang.StackTraceElement");
			Class<?> stackTraceElementArrayClass = Array.newInstance(
					stackTraceElementClass, new int[] { 0 }).getClass();

			getStackTraceMethod = Throwable.class.getMethod("getStackTrace",
					new Class[] {});

			setStackTraceMethod = Throwable.class.getMethod("setStackTrace",
					new Class[] { stackTraceElementArrayClass });

			if (getStackTraceMethod != null && setStackTraceMethod != null) {
				theStackTraceAsObject = getStackTraceMethod.invoke(sqlEx,
						new Object[0]);
				setStackTraceMethod.invoke(sqlExceptionWithNewMessage,
						new Object[] { theStackTraceAsObject });
			}
		} catch (NoClassDefFoundError noClassDefFound) {

		} catch (NoSuchMethodException noSuchMethodEx) {

		} catch (Throwable catchAll) {

		}

		return sqlExceptionWithNewMessage;
	}

	public synchronized Timer getCancelTimer() {
		if (cancelTimer == null) {
			boolean createdNamedTimer = false;
			
			// Use reflection magic to try this on JDK's 1.5 and newer, fallback to non-named
			// timer on older VMs.
			try {
				Constructor<Timer> ctr = Timer.class.getConstructor(new Class[] {String.class, Boolean.TYPE});
				
				cancelTimer = ctr.newInstance(new Object[] { "MySQL Statement Cancellation Timer", Boolean.TRUE});
				createdNamedTimer = true;
			} catch (Throwable t) {
				createdNamedTimer = false;
			}
			
			if (!createdNamedTimer) {
				cancelTimer = new Timer(true);
			}
		}
		
		return cancelTimer;
	}

	
	/**
	 * Creates a connection instance -- We need to provide factory-style methods
	 * so we can support both JDBC3 (and older) and JDBC4 runtimes, otherwise
	 * the class verifier complains when it tries to load JDBC4-only interface
	 * classes that are present in JDBC4 method signatures.
	 */

	protected static Connection getInstance(String hostToConnectTo,
			int portToConnectTo, Properties info, String databaseToConnectTo,
			String url) throws SQLException {
		if (!Util.isJdbc4()) {
			return new ConnectionImpl(hostToConnectTo, portToConnectTo, info,
					databaseToConnectTo, url);
		}

		return (Connection) Util.handleNewInstance(JDBC_4_CONNECTION_CTOR,
				new Object[] {
							hostToConnectTo, Integer.valueOf(portToConnectTo), info,
							databaseToConnectTo, url }, null);
	}

	private static final Random random = new Random();
	
	private static synchronized int getNextRoundRobinHostIndex(String url,
			List<?> hostList) {
		// we really do "random" here, because you don't get even
		// distribution when this is coupled with connection pools
		
		int indexRange = hostList.size();
		
		int index = random.nextInt(indexRange);
		
		return index;
	}

	private static boolean nullSafeCompare(String s1, String s2) {
		if (s1 == null && s2 == null) {
			return true;
		}

		if (s1 == null && s2 != null) {
			return false;
		}

		return s1 != null && s1.equals(s2);
	}

	/** Are we in autoCommit mode? */
	private boolean autoCommit = true;

	/** A map of SQL to parsed prepared statement parameters. */
	private Map<Object, Object> cachedPreparedStatementParams;

	/**
	 * For servers > 4.1.0, what character set is the metadata returned in?
	 */
	private String characterSetMetadata = null;

	/**
	 * The character set we want results and result metadata returned in (null ==
	 * results in any charset, metadata in UTF-8).
	 */
	private String characterSetResultsOnServer = null;

	/**
	 * Holds cached mappings to charset converters to avoid static
	 * synchronization and at the same time save memory (each charset converter
	 * takes approx 65K of static data).
	 */
	private Map<String, Object> charsetConverterMap = new HashMap<String, Object>(CharsetMapping
			.getNumberOfCharsetsConfigured());

	/** The point in time when this connection was created */
	private long connectionCreationTimeMillis = 0;

	/** ID used when profiling */
	private long connectionId;

	/** The database we're currently using (called Catalog in JDBC terms). */
	private String database = null;

	/** Internal DBMD to use for various database-version specific features */
	private DatabaseMetaData dbmd = null;

	private TimeZone defaultTimeZone;

	/** The event sink to use for profiling */
	private ProfilerEventHandler eventSink;

	/** Why was this connection implicitly closed, if known? (for diagnostics) */
	private Throwable forceClosedReason;

	/** Does the server suuport isolation levels? */
	private boolean hasIsolationLevels = false;

	/** Does this version of MySQL support quoted identifiers? */
	private boolean hasQuotedIdentifiers = false;

	/** The hostname we're connected to */
	private String host = null;
	
	/**
	 * We need this 'bootstrapped', because 4.1 and newer will send fields back
	 * with this even before we fill this dynamically from the server.
	 */
	public Map<Integer, String> indexToJavaCharset = new HashMap<Integer, String>();

	public Map<Integer, String> indexToCustomMysqlCharset = new HashMap<Integer, String>();

	private Map<String, Integer> mysqlCharsetToCustomMblen = new HashMap<String, Integer>();
	
	/** The I/O abstraction interface (network conn to MySQL server */
	private transient MysqlIO io = null;
	
	private boolean isClientTzUTC = false;

	/** Has this connection been closed? */
	private boolean isClosed = true;

	/** Is this connection associated with a global tx? */
	private boolean isInGlobalTx = false;

	/** Is this connection running inside a JDK-1.3 VM? */
	private boolean isRunningOnJDK13 = false;

	/** isolation level */
	private int isolationLevel = java.sql.Connection.TRANSACTION_READ_COMMITTED;

	private boolean isServerTzUTC = false;

	/** When did the last query finish? */
	private long lastQueryFinishedTime = 0;

	/** The logger we're going to use */
	private transient Log log = NULL_LOGGER;

	/**
	 * If gathering metrics, what was the execution time of the longest query so
	 * far ?
	 */
	private long longestQueryTimeMs = 0;

	/** Is the server configured to use lower-case table names only? */
	private boolean lowerCaseTableNames = false;

	/** When did the master fail? */
//	private long masterFailTimeMillis = 0L;

	private long maximumNumberTablesAccessed = 0;

	/** Has the max-rows setting been changed from the default? */
	private boolean maxRowsChanged = false;

	/** When was the last time we reported metrics? */
	private long metricsLastReportedMs;

	private long minimumNumberTablesAccessed = Long.MAX_VALUE;

	/** The JDBC URL we're using */
	private String myURL = null;

	/** Does this connection need to be tested? */
	private boolean needsPing = false;

	private int netBufferLength = 16384;

	private boolean noBackslashEscapes = false;

	private long numberOfPreparedExecutes = 0;

	private long numberOfPrepares = 0;

	private long numberOfQueriesIssued = 0;

	private long numberOfResultSetsCreated = 0;

	private long[] numTablesMetricsHistBreakpoints;

	private int[] numTablesMetricsHistCounts;

	private long[] oldHistBreakpoints = null;

	private int[] oldHistCounts = null;

	/** A map of currently open statements */
	private Map<Statement, Statement> openStatements;

	private LRUCache parsedCallableStatementCache;

	private boolean parserKnowsUnicode = false;

	/** The password we used */
	private String password = null;

	private long[] perfMetricsHistBreakpoints;

	private int[] perfMetricsHistCounts;

	/** Point of origin where this Connection was created */
	private Throwable pointOfOrigin;

	/** The port number we're connected to (defaults to 3306) */
	private int port = 3306;

	/** Properties for this connection specified by user */
	protected Properties props = null;

	/** Should we retrieve 'info' messages from the server? */
	private boolean readInfoMsg = false;

	/** Are we in read-only mode? */
	private boolean readOnly = false;

	/** Cache of ResultSet metadata */
	protected LRUCache resultSetMetadataCache;
	
	/** The timezone of the server */
	private TimeZone serverTimezoneTZ = null;

	/** The map of server variables that we retrieve at connection init. */
	private Map<String, String> serverVariables = null;

	private long shortestQueryTimeMs = Long.MAX_VALUE;

	/** A map of statements that have had setMaxRows() called on them */
	private Map<Statement, Statement> statementsUsingMaxRows;

	private double totalQueryTimeMs = 0;

	/** Are transactions supported by the MySQL server we are connected to? */
	private boolean transactionsSupported = false;

	/**
	 * The type map for UDTs (not implemented, but used by some third-party
	 * vendors, most notably IBM WebSphere)
	 */
	private Map<?, ?> typeMap;

	/** Has ANSI_QUOTES been enabled on the server? */
	private boolean useAnsiQuotes = false;

	/** The user we're connected as */
	private String user = null;
	
	/**
	 * Should we use server-side prepared statements? (auto-detected, but can be
	 * disabled by user)
	 */
	private boolean useServerPreparedStmts = false;

	private LRUCache serverSideStatementCheckCache;
	private LRUCache serverSideStatementCache;
	private Calendar sessionCalendar;
	
	private Calendar utcCalendar;
	
	private String origHostToConnectTo;

	// we don't want to be able to publicly clone this...
	
	private int origPortToConnectTo;

	private String origDatabaseToConnectTo;

	private String errorMessageEncoding = "Cp1252"; // to begin with, changes after we talk to the server
	
	private boolean usePlatformCharsetConverters;
	
	/*
	 * For testing failover scenarios
	 */
	private boolean hasTriedMasterFlag = false;

	/**
	 * The comment (if any) that we'll prepend to all statements
	 * sent to the server (to show up in "SHOW PROCESSLIST")
	 */
	private String statementComment = null;

	private boolean storesLowerCaseTableName;

	private List<StatementInterceptorV2> statementInterceptors;
	
	/**
	 * If a CharsetEncoder is required for escaping. Needed for SJIS and related
	 * problems with \u00A5.
	 */
	private boolean requiresEscapingEncoder;

	private String hostPortPair;
	
	/**'
	 * For the delegate only
	 */
	protected ConnectionImpl() {	
	}
	
	/**
	 * Creates a connection to a MySQL Server.
	 * 
	 * @param hostToConnectTo
	 *            the hostname of the database server
	 * @param portToConnectTo
	 *            the port number the server is listening on
	 * @param info
	 *            a Properties[] list holding the user and password
	 * @param databaseToConnectTo
	 *            the database to connect to
	 * @param url
	 *            the URL of the connection
	 * @param d
	 *            the Driver instantation of the connection
	 * @exception SQLException
	 *                if a database access error occurs
	 */
	protected ConnectionImpl(String hostToConnectTo, int portToConnectTo, Properties info,
			String databaseToConnectTo, String url)
			throws SQLException {
	
		this.connectionCreationTimeMillis = System.currentTimeMillis();
		this.pointOfOrigin = new Throwable();

      if (databaseToConnectTo == null) {
			databaseToConnectTo = "";
		}

		// Stash away for later, used to clone this connection for Statement.cancel
		// and Statement.setQueryTimeout().
		//
		
		this.origHostToConnectTo = hostToConnectTo;
		this.origPortToConnectTo = portToConnectTo;
		this.origDatabaseToConnectTo = databaseToConnectTo;

		try {
			Blob.class.getMethod("truncate", new Class[] {Long.TYPE});
			
			this.isRunningOnJDK13 = false;
		} catch (NoSuchMethodException nsme) {
			this.isRunningOnJDK13 = true;
		}
		
		this.sessionCalendar = new GregorianCalendar();
		this.utcCalendar = new GregorianCalendar();
		this.utcCalendar.setTimeZone(TimeZone.getTimeZone("GMT"));
		
		//
		// Normally, this code would be in initializeDriverProperties,
		// but we need to do this as early as possible, so we can start
		// logging to the 'correct' place as early as possible...this.log
		// points to 'NullLogger' for every connection at startup to avoid
		// NPEs and the overhead of checking for NULL at every logging call.
		//
		// We will reset this to the configured logger during properties
		// initialization.
		//
		this.log = LogFactory.getLogger(getLogger(), LOGGER_INSTANCE_NAME, getExceptionInterceptor());

		// We store this per-connection, due to static synchronization
		// issues in Java's built-in TimeZone class...
		this.defaultTimeZone = Util.getDefaultTimeZone();
		
		if ("GMT".equalsIgnoreCase(this.defaultTimeZone.getID())) {
			this.isClientTzUTC = true;
		} else {
			this.isClientTzUTC = false;
		}

		this.openStatements = new HashMap<Statement, Statement>();
		
		if (NonRegisteringDriver.isHostPropertiesList(hostToConnectTo)) {
			Properties hostSpecificProps = NonRegisteringDriver.expandHostKeyValues(hostToConnectTo);
			
			Enumeration<?> propertyNames = hostSpecificProps.propertyNames();
			
			while (propertyNames.hasMoreElements()) {
				String propertyName = propertyNames.nextElement().toString();
				String propertyValue = hostSpecificProps.getProperty(propertyName);
				
				info.setProperty(propertyName, propertyValue);
			}
		} else {
		
			if (hostToConnectTo == null) {
				this.host = "localhost";
				this.hostPortPair = this.host + ":" + portToConnectTo;
			} else {
				this.host = hostToConnectTo;
				
				if (hostToConnectTo.indexOf(":") == -1) {
					this.hostPortPair = this.host + ":" + portToConnectTo;
				} else {
					this.hostPortPair = this.host;
				}
			}
		}

		this.port = portToConnectTo;

		this.database = databaseToConnectTo;
		this.myURL = url;
		this.user = info.getProperty(NonRegisteringDriver.USER_PROPERTY_KEY);
		this.password = info
				.getProperty(NonRegisteringDriver.PASSWORD_PROPERTY_KEY);

		if ((this.user == null) || this.user.equals("")) {
			this.user = "";
		}

		if (this.password == null) {
			this.password = "";
		}

		this.props = info;
		
		
		
		initializeDriverProperties(info);
		
		
		try {
			this.dbmd = getMetaData(false, false);
			initializeSafeStatementInterceptors();
			createNewIO(false);
			unSafeStatementInterceptors();
		} catch (SQLException ex) {
			cleanup(ex);

			// don't clobber SQL exceptions
			throw ex;
		} catch (Exception ex) {
			cleanup(ex);

			StringBuffer mesg = new StringBuffer(128);

			if (!getParanoid()) {
				mesg.append("Cannot connect to MySQL server on ");
				mesg.append(this.host);
				mesg.append(":");
				mesg.append(this.port);
				mesg.append(".\n\n");
				mesg.append("Make sure that there is a MySQL server ");
				mesg.append("running on the machine/port you are trying ");
				mesg
						.append("to connect to and that the machine this software is "
								+ "running on ");
				mesg.append("is able to connect to this host/port "
						+ "(i.e. not firewalled). ");
				mesg
						.append("Also make sure that the server has not been started "
								+ "with the --skip-networking ");
				mesg.append("flag.\n\n");
			} else {
				mesg.append("Unable to connect to database.");
			}

			SQLException sqlEx = SQLError.createSQLException(mesg.toString(),
					SQLError.SQL_STATE_COMMUNICATION_LINK_FAILURE, getExceptionInterceptor());
			
			sqlEx.initCause(ex);
			
			throw sqlEx;
		}
	}

    public void unSafeStatementInterceptors() throws SQLException {
    	
    	ArrayList<StatementInterceptorV2> unSafedStatementInterceptors = new ArrayList<StatementInterceptorV2>(this.statementInterceptors.size());

    	for (int i = 0; i < this.statementInterceptors.size(); i++) {
    		NoSubInterceptorWrapper wrappedInterceptor = (NoSubInterceptorWrapper) this.statementInterceptors.get(i);
    		
    		unSafedStatementInterceptors.add(wrappedInterceptor.getUnderlyingInterceptor());
    	}
    	
    	this.statementInterceptors = unSafedStatementInterceptors;
    	
    	if (this.io != null) {
    		this.io.setStatementInterceptors(this.statementInterceptors);
    	}
	}
    
    public void initializeSafeStatementInterceptors() throws SQLException {
    	this.isClosed = false;
    	
    	List<Extension> unwrappedInterceptors = Util.loadExtensions(this, this.props, 
				getStatementInterceptors(),
				"MysqlIo.BadStatementInterceptor", getExceptionInterceptor());
    	
    	this.statementInterceptors = new ArrayList<StatementInterceptorV2>(unwrappedInterceptors.size());

    	for (int i = 0; i < unwrappedInterceptors.size(); i++) {
    		Extension interceptor = unwrappedInterceptors.get(i);
    		
    		// adapt older versions of statement interceptors, handle the case where something wants v2
    		// functionality but wants to run with an older driver
    		if (interceptor instanceof StatementInterceptor) {
    			if (ReflectiveStatementInterceptorAdapter.getV2PostProcessMethod(interceptor.getClass()) != null) {
    				this.statementInterceptors.add(new NoSubInterceptorWrapper(new ReflectiveStatementInterceptorAdapter((StatementInterceptor) interceptor)));
    			} else {
    				this.statementInterceptors.add(new NoSubInterceptorWrapper(new V1toV2StatementInterceptorAdapter((StatementInterceptor) interceptor)));
    			}
    		} else {
    			this.statementInterceptors.add(new NoSubInterceptorWrapper((StatementInterceptorV2)interceptor));
    		}
    	}
    	
    	
    }
    
    public List<StatementInterceptorV2> getStatementInterceptorsInstances() {
    	return this.statementInterceptors;
    }
    
	private void addToHistogram(int[] histogramCounts,
			long[] histogramBreakpoints, long value, int numberOfTimes,
			long currentLowerBound, long currentUpperBound) {
		if (histogramCounts == null) {
			createInitialHistogram(histogramBreakpoints,
					currentLowerBound, currentUpperBound);
		} else {
			for (int i = 0; i < HISTOGRAM_BUCKETS; i++) {
				if (histogramBreakpoints[i] >= value) {
					histogramCounts[i] += numberOfTimes;
	
					break;
				}
			}
		}
	}

	private void addToPerformanceHistogram(long value, int numberOfTimes) {
		checkAndCreatePerformanceHistogram();

		addToHistogram(this.perfMetricsHistCounts,
				this.perfMetricsHistBreakpoints, value, numberOfTimes,
				this.shortestQueryTimeMs == Long.MAX_VALUE ? 0
						: this.shortestQueryTimeMs, this.longestQueryTimeMs);
	}

	private void addToTablesAccessedHistogram(long value, int numberOfTimes) {
		checkAndCreateTablesAccessedHistogram();

		addToHistogram(this.numTablesMetricsHistCounts,
				this.numTablesMetricsHistBreakpoints, value, numberOfTimes,
				this.minimumNumberTablesAccessed == Long.MAX_VALUE ? 0
						: this.minimumNumberTablesAccessed,
				this.maximumNumberTablesAccessed);
	}
	
	/**
	 * Builds the map needed for 4.1.0 and newer servers that maps field-level
	 * charset/collation info to a java character encoding name.
	 * 
	 * @throws SQLException
	 *             DOCUMENT ME!
	 */
	private void buildCollationMapping() throws SQLException {

		HashMap<Integer, String> javaCharset = null;

		if (versionMeetsMinimum(4, 1, 0)) {

			TreeMap<Long, String> sortedCollationMap = null;
			HashMap<Integer, String> customCharset = null;
			HashMap<String, Integer> customMblen = null;

			if (getCacheServerConfiguration()) {
				synchronized (serverConfigByUrl) {
					sortedCollationMap = (TreeMap<Long, String>) serverCollationByUrl.get(getURL());
					javaCharset = (HashMap<Integer, String>) serverJavaCharsetByUrl.get(getURL());
					customCharset = (HashMap<Integer, String>) serverCustomCharsetByUrl.get(getURL());
					customMblen = (HashMap<String, Integer>) serverCustomMblenByUrl.get(getURL());
				}
			}

			java.sql.Statement stmt = null;
			java.sql.ResultSet results = null;

			try {
				if (sortedCollationMap == null) {
					sortedCollationMap = new TreeMap<Long, String>();
					javaCharset = new HashMap<Integer, String>();
					customCharset = new HashMap<Integer, String>();
					customMblen = new HashMap<String, Integer>();

					stmt = getMetadataSafeStatement();

					results = stmt.executeQuery("SHOW COLLATION");
					if (versionMeetsMinimum(5, 0, 0)) {
						Util.resultSetToMap(sortedCollationMap, results, 3, 2);
					} else {
						while (results.next()) {
							sortedCollationMap.put(results.getLong(3), results.getString(2));
						}
					}

					for (Iterator<Map.Entry<Long, String>> indexIter = sortedCollationMap.entrySet().iterator(); indexIter.hasNext();) {
						Map.Entry<Long, String> indexEntry = indexIter.next();

						int collationIndex = indexEntry.getKey().intValue();
						String charsetName = indexEntry.getValue();

						javaCharset.put(collationIndex, getJavaEncodingForMysqlEncoding(charsetName));

						// if no static map for charsetIndex
						// or server has a different mapping then our static map,
						// adding it to custom map 
						if (collationIndex >= CharsetMapping.MAP_SIZE ||
							!charsetName.equals(CharsetMapping.STATIC_INDEX_TO_MYSQL_CHARSET_MAP.get(collationIndex))) {
							customCharset.put(collationIndex, charsetName);
						}

						// if no static map for charsetName adding to custom map
						if (!CharsetMapping.STATIC_CHARSET_TO_NUM_BYTES_MAP.containsKey(charsetName) &&
							!CharsetMapping.STATIC_4_0_CHARSET_TO_NUM_BYTES_MAP.containsKey(charsetName)) {
							customMblen.put(charsetName, null);
						}
					}
					
					// if there is a number of custom charsets we should execute SHOW CHARACTER SET to know theirs mblen
					if (customMblen.size() > 0) {
						results = stmt.executeQuery("SHOW CHARACTER SET");
						while (results.next()) {
							String charsetName = results.getString("Charset");
							if (customMblen.containsKey(charsetName)) {
								customMblen.put(charsetName, results.getInt("Maxlen"));
							}
						}
					}

					if (getCacheServerConfiguration()) {
						synchronized (serverConfigByUrl) {
							serverCollationByUrl.put(getURL(), sortedCollationMap);
							serverJavaCharsetByUrl.put(getURL(), javaCharset);
							serverCustomCharsetByUrl.put(getURL(), customCharset);
							serverCustomMblenByUrl.put(getURL(), customMblen);
						}
					}

				}

				this.indexToJavaCharset = Collections.unmodifiableMap(javaCharset);
				this.indexToCustomMysqlCharset = Collections.unmodifiableMap(customCharset);
				this.mysqlCharsetToCustomMblen = Collections.unmodifiableMap(customMblen);
				
			} catch (SQLException ex) {
				throw ex;
			} catch (RuntimeException ex) {
				SQLException sqlEx = SQLError.createSQLException(ex.toString(), SQLError.SQL_STATE_ILLEGAL_ARGUMENT, null);
				sqlEx.initCause(ex);
				throw sqlEx;
			} finally {
				if (results != null) {
					try {
						results.close();
					} catch (java.sql.SQLException sqlE) {
						// ignore
					}
				}

				if (stmt != null) {
					try {
						stmt.close();
					} catch (java.sql.SQLException sqlE) {
						// ignore
					}
				}
			}
		} else {
			javaCharset = new HashMap<Integer, String>();
			for (int i = 0; i < CharsetMapping.INDEX_TO_CHARSET.length; i++) {
				javaCharset.put(i, CharsetMapping.INDEX_TO_CHARSET[i]);
			}
			this.indexToJavaCharset = Collections.unmodifiableMap(javaCharset);
		}
	}

	public String getJavaEncodingForMysqlEncoding(String mysqlEncoding) throws SQLException {
		
		if (versionMeetsMinimum(4, 1, 0) && "latin1".equalsIgnoreCase(mysqlEncoding)) {
			return "Cp1252";
		}
		
		return CharsetMapping.MYSQL_TO_JAVA_CHARSET_MAP.get(mysqlEncoding);
	}

	private boolean canHandleAsServerPreparedStatement(String sql) 
		throws SQLException {
		if (sql == null || sql.length() == 0) {
			return true;
		}

		if (!this.useServerPreparedStmts) {
			return false;
		}
		
		if (getCachePreparedStatements()) {
			synchronized (this.serverSideStatementCheckCache) {
				Boolean flag = (Boolean)this.serverSideStatementCheckCache.get(sql);
				
				if (flag != null) {
					return flag.booleanValue();
				}
					
				boolean canHandle = canHandleAsServerPreparedStatementNoCache(sql);
				
				if (sql.length() < getPreparedStatementCacheSqlLimit()) {
					this.serverSideStatementCheckCache.put(sql, 
							canHandle ? Boolean.TRUE : Boolean.FALSE);
				}
					
				return canHandle;
			}
		}
		
		return canHandleAsServerPreparedStatementNoCache(sql);
	}

	private boolean canHandleAsServerPreparedStatementNoCache(String sql) 
		throws SQLException {
		
		// Can't use server-side prepare for CALL
		if (StringUtils.startsWithIgnoreCaseAndNonAlphaNumeric(sql, "CALL")) {
			return false;
		}
		
		boolean canHandleAsStatement = true;
		
		if (!versionMeetsMinimum(5, 0, 7) && 
				(StringUtils.startsWithIgnoreCaseAndNonAlphaNumeric(sql, "SELECT")
				|| StringUtils.startsWithIgnoreCaseAndNonAlphaNumeric(sql,
						"DELETE")
				|| StringUtils.startsWithIgnoreCaseAndNonAlphaNumeric(sql,
						"INSERT")
				|| StringUtils.startsWithIgnoreCaseAndNonAlphaNumeric(sql,
						"UPDATE")
				|| StringUtils.startsWithIgnoreCaseAndNonAlphaNumeric(sql,
						"REPLACE"))) {

			// check for limit ?[,?]

			/*
			 * The grammar for this (from the server) is: ULONG_NUM | ULONG_NUM
			 * ',' ULONG_NUM | ULONG_NUM OFFSET_SYM ULONG_NUM
			 */

			int currentPos = 0;
			int statementLength = sql.length();
			int lastPosToLook = statementLength - 7; // "LIMIT ".length()
			boolean allowBackslashEscapes = !this.noBackslashEscapes;
			char quoteChar = this.useAnsiQuotes ? '"' : '\'';
			boolean foundLimitWithPlaceholder = false;

			while (currentPos < lastPosToLook) {
				int limitStart = StringUtils.indexOfIgnoreCaseRespectQuotes(
						currentPos, sql, "LIMIT ", quoteChar,
						allowBackslashEscapes);

				if (limitStart == -1) {
					break;
				}

				currentPos = limitStart + 7;

				while (currentPos < statementLength) {
					char c = sql.charAt(currentPos);

					//
					// Have we reached the end
					// of what can be in a LIMIT clause?
					//

					if (!Character.isDigit(c) && !Character.isWhitespace(c)
							&& c != ',' && c != '?') {
						break;
					}

					if (c == '?') {
						foundLimitWithPlaceholder = true;
						break;
					}

					currentPos++;
				}
			}

			canHandleAsStatement = !foundLimitWithPlaceholder;
		} else if (StringUtils.startsWithIgnoreCaseAndWs(sql, "CREATE TABLE")) {
			canHandleAsStatement = false;
		} else if (StringUtils.startsWithIgnoreCaseAndWs(sql, "DO")) {
			canHandleAsStatement = false;
		} else if (StringUtils.startsWithIgnoreCaseAndWs(sql, "SET")) {
			canHandleAsStatement = false;
		}

		
		
		return canHandleAsStatement;
	}

	/**
	 * Changes the user on this connection by performing a re-authentication. If
	 * authentication fails, the connection will remain under the context of the
	 * current user.
	 * 
	 * @param userName
	 *            the username to authenticate with
	 * @param newPassword
	 *            the password to authenticate with
	 * @throws SQLException
	 *             if authentication fails, or some other error occurs while
	 *             performing the command.
	 */
	public synchronized void changeUser(String userName, String newPassword)
			throws SQLException {
		checkClosed();
		
		if ((userName == null) || userName.equals("")) {
			userName = "";
		}

		if (newPassword == null) {
			newPassword = "";
		}

		this.io.changeUser(userName, newPassword, this.database);
		this.user = userName;
		this.password = newPassword;

		if (versionMeetsMinimum(4, 1, 0)) {
			configureClientCharacterSet(true);
		}
		
		setSessionVariables();
		
		setupServerForTruncationChecks();
	}

	private boolean characterSetNamesMatches(String mysqlEncodingName) {
		// set names is equivalent to character_set_client ..._results and ..._connection,
		// but we set _results later, so don't check it here.
		return (mysqlEncodingName != null && 
				mysqlEncodingName.equalsIgnoreCase(this.serverVariables.get("character_set_client")) &&
				mysqlEncodingName.equalsIgnoreCase(this.serverVariables.get("character_set_connection")));
	}

	private void checkAndCreatePerformanceHistogram() {
		if (this.perfMetricsHistCounts == null) {
			this.perfMetricsHistCounts = new int[HISTOGRAM_BUCKETS];
		}

		if (this.perfMetricsHistBreakpoints == null) {
			this.perfMetricsHistBreakpoints = new long[HISTOGRAM_BUCKETS];
		}
	}

	private void checkAndCreateTablesAccessedHistogram() {
		if (this.numTablesMetricsHistCounts == null) {
			this.numTablesMetricsHistCounts = new int[HISTOGRAM_BUCKETS];
		}

		if (this.numTablesMetricsHistBreakpoints == null) {
			this.numTablesMetricsHistBreakpoints = new long[HISTOGRAM_BUCKETS];
		}
	}

	public void checkClosed() throws SQLException {
		if (this.isClosed) {
			throwConnectionClosedException();
		}
	}

	public void throwConnectionClosedException() throws SQLException {
		StringBuffer messageBuf = new StringBuffer(
				"No operations allowed after connection closed.");

		SQLException ex = SQLError.createSQLException(messageBuf.toString(),
				SQLError.SQL_STATE_CONNECTION_NOT_OPEN, getExceptionInterceptor());
		
		if (this.forceClosedReason != null) {
			ex.initCause(this.forceClosedReason);
		}

		throw ex;
	}

	/**
	 * If useUnicode flag is set and explicit client character encoding isn't
	 * specified then assign encoding from server if any.
	 * 
	 * @throws SQLException
	 *             DOCUMENT ME!
	 */
	private void checkServerEncoding() throws SQLException {
		if (getUseUnicode() && (getEncoding() != null)) {
			// spec'd by client, don't map
			return;
		}

		String serverEncoding = this.serverVariables.get("character_set");

		if (serverEncoding == null) {
			// must be 4.1.1 or newer?
			serverEncoding = this.serverVariables.get("character_set_server");
		}

		String mappedServerEncoding = null;

		if (serverEncoding != null) {
			try {
				mappedServerEncoding = getJavaEncodingForMysqlEncoding(serverEncoding
							.toUpperCase(Locale.ENGLISH));
			} catch (SQLException ex) {
				throw ex;
			} catch (RuntimeException ex) {
				SQLException sqlEx = SQLError.createSQLException(ex.toString(), SQLError.SQL_STATE_ILLEGAL_ARGUMENT, null);
				sqlEx.initCause(ex);
				throw sqlEx;
			}
		}

		//
		// First check if we can do the encoding ourselves
		//
		if (!getUseUnicode() && (mappedServerEncoding != null)) {
			SingleByteCharsetConverter converter = getCharsetConverter(mappedServerEncoding);

			if (converter != null) { // we know how to convert this ourselves
				setUseUnicode(true); // force the issue
				setEncoding(mappedServerEncoding);

				return;
			}
		}

		//
		// Now, try and find a Java I/O converter that can do
		// the encoding for us
		//
		if (serverEncoding != null) {
			if (mappedServerEncoding == null) {
				// We don't have a mapping for it, so try
				// and canonicalize the name....
				if (Character.isLowerCase(serverEncoding.charAt(0))) {
					char[] ach = serverEncoding.toCharArray();
					ach[0] = Character.toUpperCase(serverEncoding.charAt(0));
					setEncoding(new String(ach));
				}
			}

			if (mappedServerEncoding == null) {
				throw SQLError.createSQLException("Unknown character encoding on server '"
						+ serverEncoding
						+ "', use 'characterEncoding=' property "
						+ " to provide correct mapping",
						SQLError.SQL_STATE_INVALID_CONNECTION_ATTRIBUTE, getExceptionInterceptor());
			}

			//
			// Attempt to use the encoding, and bail out if it
			// can't be used
			//
			try {
				StringUtils.getBytes("abc",mappedServerEncoding);
				setEncoding(mappedServerEncoding);
				setUseUnicode(true);
			} catch (UnsupportedEncodingException UE) {
				throw SQLError.createSQLException(
						"The driver can not map the character encoding '"
								+ getEncoding()
								+ "' that your server is using "
								+ "to a character encoding your JVM understands. You "
								+ "can specify this mapping manually by adding \"useUnicode=true\" "
								+ "as well as \"characterEncoding=[an_encoding_your_jvm_understands]\" "
								+ "to your JDBC URL.", "0S100", getExceptionInterceptor());
			}
		}
	}

	/**
	 * Set transaction isolation level to the value received from server if any.
	 * Is called by connectionInit(...)
	 * 
	 * @throws SQLException
	 *             DOCUMENT ME!
	 */
	private void checkTransactionIsolationLevel() throws SQLException {
		String txIsolationName = null;

		if (versionMeetsMinimum(4, 0, 3)) {
			txIsolationName = "tx_isolation";
		} else {
			txIsolationName = "transaction_isolation";
		}

		String s = this.serverVariables.get(txIsolationName);

		if (s != null) {
			Integer intTI = mapTransIsolationNameToValue.get(s);

			if (intTI != null) {
				this.isolationLevel = intTI.intValue();
			}
		}
	}

	/**
	 * Clobbers the physical network connection and marks
	 * this connection as closed.
	 * 
	 * @throws SQLException
	 */
	public void abortInternal() throws SQLException {
		if (this.io != null) {
			try {
				this.io.forceClose();
			} catch (Throwable t) {
				// can't do anything about it, and we're forcibly aborting
			}
			this.io = null;
		}
		
		this.isClosed = true;
	}
	
	/**
	 * Destroys this connection and any underlying resources
	 * 
	 * @param fromWhere
	 *            DOCUMENT ME!
	 * @param whyCleanedUp
	 *            DOCUMENT ME!
	 */
	private void cleanup(Throwable whyCleanedUp) {
		try {
			if ((this.io != null) && !isClosed()) {
				realClose(false, false, false, whyCleanedUp);
			} else if (this.io != null) {
				this.io.forceClose();
			}
		} catch (SQLException sqlEx) {
			// ignore, we're going away.
			;
		}

		this.isClosed = true;
	}

	public void clearHasTriedMaster() {
		this.hasTriedMasterFlag = false;
	}
	
	/**
	 * After this call, getWarnings returns null until a new warning is reported
	 * for this connection.
	 * 
	 * @exception SQLException
	 *                if a database access error occurs
	 */
	public void clearWarnings() throws SQLException {
		// firstWarning = null;
	}

	/**
	 * DOCUMENT ME!
	 * 
	 * @param sql
	 *            DOCUMENT ME!
	 * @return DOCUMENT ME!
	 * @throws SQLException
	 *             DOCUMENT ME!
	 */
	public java.sql.PreparedStatement clientPrepareStatement(String sql)
			throws SQLException {
		return clientPrepareStatement(sql,
				DEFAULT_RESULT_SET_TYPE,
				DEFAULT_RESULT_SET_CONCURRENCY);
	}

	/**
	 * @see Connection#prepareStatement(String, int)
	 */
	public java.sql.PreparedStatement clientPrepareStatement(String sql,
			int autoGenKeyIndex) throws SQLException {
		java.sql.PreparedStatement pStmt = clientPrepareStatement(sql);

		((com.mysql.jdbc.PreparedStatement) pStmt)
				.setRetrieveGeneratedKeys(autoGenKeyIndex == java.sql.Statement.RETURN_GENERATED_KEYS);

		return pStmt;
	}

	/**
	 * DOCUMENT ME!
	 * 
	 * @param sql
	 *            DOCUMENT ME!
	 * @param resultSetType
	 *            DOCUMENT ME!
	 * @param resultSetConcurrency
	 *            DOCUMENT ME!
	 * @return DOCUMENT ME!
	 * @throws SQLException
	 *             DOCUMENT ME!
	 */
	public java.sql.PreparedStatement clientPrepareStatement(String sql,
			int resultSetType, int resultSetConcurrency) throws SQLException {
		return clientPrepareStatement(sql, resultSetType, resultSetConcurrency, true);
	}


	
	public java.sql.PreparedStatement clientPrepareStatement(String sql,
			int resultSetType, int resultSetConcurrency, 
			boolean processEscapeCodesIfNeeded) throws SQLException {
		checkClosed();

		String nativeSql = processEscapeCodesIfNeeded && getProcessEscapeCodesForPrepStmts() ? nativeSQL(sql): sql;
		
		PreparedStatement pStmt = null;

		if (getCachePreparedStatements()) {
			synchronized (this.cachedPreparedStatementParams) {
				PreparedStatement.ParseInfo pStmtInfo = (PreparedStatement.ParseInfo) this.cachedPreparedStatementParams
						.get(nativeSql);
	
				if (pStmtInfo == null) {
					pStmt = com.mysql.jdbc.PreparedStatement.getInstance(getLoadBalanceSafeProxy(), nativeSql,
							this.database);
	
					PreparedStatement.ParseInfo parseInfo = pStmt.getParseInfo();
	
					if (parseInfo.statementLength < getPreparedStatementCacheSqlLimit()) {
						if (this.cachedPreparedStatementParams.size() >= getPreparedStatementCacheSize()) {
							Iterator<Object> oldestIter = this.cachedPreparedStatementParams
									.keySet().iterator();
							long lruTime = Long.MAX_VALUE;
							String oldestSql = null;
	
							while (oldestIter.hasNext()) {
								String sqlKey = (String) oldestIter.next();
								PreparedStatement.ParseInfo lruInfo = (PreparedStatement.ParseInfo) this.cachedPreparedStatementParams
										.get(sqlKey);
	
								if (lruInfo.lastUsed < lruTime) {
									lruTime = lruInfo.lastUsed;
									oldestSql = sqlKey;
								}
							}
	
							if (oldestSql != null) {
								this.cachedPreparedStatementParams
										.remove(oldestSql);
							}
						}
	
						this.cachedPreparedStatementParams.put(nativeSql, pStmt
								.getParseInfo());
					}
				} else {
					pStmtInfo.lastUsed = System.currentTimeMillis();
					pStmt = new com.mysql.jdbc.PreparedStatement(getLoadBalanceSafeProxy(), nativeSql,
							this.database, pStmtInfo);
				}
			}
		} else {
			pStmt = com.mysql.jdbc.PreparedStatement.getInstance(getLoadBalanceSafeProxy(), nativeSql,
					this.database);
		}

		pStmt.setResultSetType(resultSetType);
		pStmt.setResultSetConcurrency(resultSetConcurrency);

		return pStmt;
	}
	
	/**
	 * @see java.sql.Connection#prepareStatement(String, int[])
	 */
	public java.sql.PreparedStatement clientPrepareStatement(String sql,
			int[] autoGenKeyIndexes) throws SQLException {
		
		PreparedStatement pStmt = (PreparedStatement) clientPrepareStatement(sql);
		
		pStmt
				.setRetrieveGeneratedKeys((autoGenKeyIndexes != null)
						&& (autoGenKeyIndexes.length > 0));

		return pStmt;
	}

	/**
	 * @see java.sql.Connection#prepareStatement(String, String[])
	 */
	public java.sql.PreparedStatement clientPrepareStatement(String sql,
			String[] autoGenKeyColNames) throws SQLException {
		PreparedStatement pStmt = (PreparedStatement) clientPrepareStatement(sql);

		pStmt
				.setRetrieveGeneratedKeys((autoGenKeyColNames != null)
						&& (autoGenKeyColNames.length > 0));

		return pStmt;
	}

	public java.sql.PreparedStatement clientPrepareStatement(String sql,
			int resultSetType, int resultSetConcurrency,
			int resultSetHoldability) throws SQLException {
		return clientPrepareStatement(sql, resultSetType, resultSetConcurrency, true);
	}
	
	// --------------------------JDBC 2.0-----------------------------

	/**
	 * In some cases, it is desirable to immediately release a Connection's
	 * database and JDBC resources instead of waiting for them to be
	 * automatically released (cant think why off the top of my head) <B>Note:</B>
	 * A Connection is automatically closed when it is garbage collected.
	 * Certain fatal errors also result in a closed connection.
	 * 
	 * @exception SQLException
	 *                if a database access error occurs
	 */
	public synchronized void close() throws SQLException {
		if (this.connectionLifecycleInterceptors != null) {
			new IterateBlock(this.connectionLifecycleInterceptors.iterator()) {
				void forEach(Object each) throws SQLException {
					((ConnectionLifecycleInterceptor)each).close();
				}
			}.doForAll();
		}
	
		realClose(true, true, false, null);
	}

	/**
	 * Closes all currently open statements.
	 * 
	 * @throws SQLException
	 *             DOCUMENT ME!
	 */
	private void closeAllOpenStatements() throws SQLException {
		SQLException postponedException = null;

		if (this.openStatements != null) {
			List<Statement> currentlyOpenStatements = new ArrayList<Statement>(); // we need this to
			// avoid
			// ConcurrentModificationEx

			for (Iterator<Statement> iter = this.openStatements.keySet().iterator(); iter.hasNext();) {
				currentlyOpenStatements.add(iter.next());
			}

			int numStmts = currentlyOpenStatements.size();

			for (int i = 0; i < numStmts; i++) {
				StatementImpl stmt = (StatementImpl) currentlyOpenStatements.get(i);

				try {
					stmt.realClose(false, true);
				} catch (SQLException sqlEx) {
					postponedException = sqlEx; // throw it later, cleanup all
					// statements first
				}
			}

			if (postponedException != null) {
				throw postponedException;
			}
		}
	}

	private void closeStatement(java.sql.Statement stmt) {
		if (stmt != null) {
			try {
				stmt.close();
			} catch (SQLException sqlEx) {
				; // ignore
			}

			stmt = null;
		}
	}

	/**
	 * The method commit() makes all changes made since the previous
	 * commit/rollback permanent and releases any database locks currently held
	 * by the Connection. This method should only be used when auto-commit has
	 * been disabled.
	 * <p>
	 * <b>Note:</b> MySQL does not support transactions, so this method is a
	 * no-op.
	 * </p>
	 * 
	 * @exception SQLException
	 *                if a database access error occurs
	 * @see setAutoCommit
	 */
	public synchronized void commit() throws SQLException {
		checkClosed();

		try {
			if (this.connectionLifecycleInterceptors != null) {
				IterateBlock iter = new IterateBlock(this.connectionLifecycleInterceptors.iterator()) {

					void forEach(Object each) throws SQLException {
						if (!((ConnectionLifecycleInterceptor)each).commit()) {
							this.stopIterating = true;
						}
					}
				};
				
				iter.doForAll();
				
				if (!iter.fullIteration()) {
					return;
				}
			}
			
			// no-op if _relaxAutoCommit == true
			if (this.autoCommit && !getRelaxAutoCommit()) {
				throw SQLError.createSQLException("Can't call commit when autocommit=true", getExceptionInterceptor());
			} else if (this.transactionsSupported) {
				if (getUseLocalTransactionState() && versionMeetsMinimum(5, 0, 0)) {
					if (!this.io.inTransactionOnServer()) {
						return; // effectively a no-op
					}
				}

				execSQL(null, "commit", -1, null,
						DEFAULT_RESULT_SET_TYPE,
						DEFAULT_RESULT_SET_CONCURRENCY, false,
						this.database, null,
						false);
			}
		} catch (SQLException sqlException) {
			if (SQLError.SQL_STATE_COMMUNICATION_LINK_FAILURE
					.equals(sqlException.getSQLState())) {
				throw SQLError
						.createSQLException(
								"Communications link failure during commit(). Transaction resolution unknown.",
								SQLError.SQL_STATE_TRANSACTION_RESOLUTION_UNKNOWN,
								getExceptionInterceptor());
			}

			throw sqlException;
		} finally {
			this.needsPing = this.getReconnectAtTxEnd();
		}

		return;
	}
	
	/**
	 * Configures client-side properties for character set information.
	 * 
	 * @throws SQLException
	 *             if unable to configure the specified character set.
	 */
	private void configureCharsetProperties() throws SQLException {
		if (getEncoding() != null) {
			// Attempt to use the encoding, and bail out if it
			// can't be used
			try {
				String testString = "abc";
				StringUtils.getBytes(testString, getEncoding());
			} catch (UnsupportedEncodingException UE) {
				// Try the MySQL character encoding, then....
				String oldEncoding = getEncoding();

				try {
					setEncoding(getJavaEncodingForMysqlEncoding(oldEncoding));
				} catch (SQLException ex) {
					throw ex;
				} catch (RuntimeException ex) {
					SQLException sqlEx = SQLError.createSQLException(ex.toString(), SQLError.SQL_STATE_ILLEGAL_ARGUMENT, null);
					sqlEx.initCause(ex);
					throw sqlEx;
				}

				if (getEncoding() == null) {
					throw SQLError.createSQLException(
							"Java does not support the MySQL character encoding "
									+ " " + "encoding '" + oldEncoding + "'.",
							SQLError.SQL_STATE_INVALID_CONNECTION_ATTRIBUTE, getExceptionInterceptor());
				}

				try {
					String testString = "abc";
					StringUtils.getBytes(testString, getEncoding());
				} catch (UnsupportedEncodingException encodingEx) {
					throw SQLError.createSQLException("Unsupported character "
							+ "encoding '" + getEncoding() + "'.",
							SQLError.SQL_STATE_INVALID_CONNECTION_ATTRIBUTE, getExceptionInterceptor());
				}
			}
		}
	}

	/**
	 * Sets up client character set for MySQL-4.1 and newer if the user This
	 * must be done before any further communication with the server!
	 * 
	 * @return true if this routine actually configured the client character
	 *         set, or false if the driver needs to use 'older' methods to
	 *         detect the character set, as it is connected to a MySQL server
	 *         older than 4.1.0
	 * @throws SQLException
	 *             if an exception happens while sending 'SET NAMES' to the
	 *             server, or the server sends character set information that
	 *             the client doesn't know about.
	 */
	private boolean configureClientCharacterSet(boolean dontCheckServerMatch) throws SQLException {
		String realJavaEncoding = getEncoding();
		boolean characterSetAlreadyConfigured = false;

		try {
			if (versionMeetsMinimum(4, 1, 0)) {
				characterSetAlreadyConfigured = true;

				setUseUnicode(true);

				configureCharsetProperties();
				realJavaEncoding = getEncoding(); // we need to do this again
				// to grab this for
				// versions > 4.1.0

				try {

					// Fault injection for testing server character set indices
		            
		            if (props != null && props.getProperty("com.mysql.jdbc.faultInjection.serverCharsetIndex") != null) {
		            	this.io.serverCharsetIndex = Integer.parseInt(
		            			props.getProperty(
		            					"com.mysql.jdbc.faultInjection.serverCharsetIndex"));	
		            }
		            
					String serverEncodingToSet = 
						CharsetMapping.INDEX_TO_CHARSET[this.io.serverCharsetIndex];
					
					if (serverEncodingToSet == null || serverEncodingToSet.length() == 0) {
						if (realJavaEncoding != null) {
							// user knows best, try it
							setEncoding(realJavaEncoding);
						} else {
							throw SQLError.createSQLException(
									"Unknown initial character set index '"
											+ this.io.serverCharsetIndex
											+ "' received from server. Initial client character set can be forced via the 'characterEncoding' property.",
									SQLError.SQL_STATE_GENERAL_ERROR, getExceptionInterceptor());
						}
					}
					
					// "latin1" on MySQL-4.1.0+ is actually CP1252, not ISO8859_1
					if (versionMeetsMinimum(4, 1, 0) && 
							"ISO8859_1".equalsIgnoreCase(serverEncodingToSet)) {
						serverEncodingToSet = "Cp1252";
					}
					
					setEncoding(serverEncodingToSet);
				
				} catch (ArrayIndexOutOfBoundsException outOfBoundsEx) {
					if (realJavaEncoding != null) {
						// user knows best, try it
						setEncoding(realJavaEncoding);
					} else {
						throw SQLError.createSQLException(
								"Unknown initial character set index '"
										+ this.io.serverCharsetIndex
										+ "' received from server. Initial client character set can be forced via the 'characterEncoding' property.",
								SQLError.SQL_STATE_GENERAL_ERROR, getExceptionInterceptor());
					}
				} catch (SQLException ex) {
					throw ex;
				} catch (RuntimeException ex) {
					SQLException sqlEx = SQLError.createSQLException(ex.toString(), SQLError.SQL_STATE_ILLEGAL_ARGUMENT, null);
					sqlEx.initCause(ex);
					throw sqlEx;
				}

				if (getEncoding() == null) {
					// punt?
					setEncoding("ISO8859_1");
				}

				//
				// Has the user has 'forced' the character encoding via
				// driver properties?
				//
				if (getUseUnicode()) {
					if (realJavaEncoding != null) {

						//
						// Now, inform the server what character set we
						// will be using from now-on...
						//
						if (realJavaEncoding.equalsIgnoreCase("UTF-8")
								|| realJavaEncoding.equalsIgnoreCase("UTF8")) {
							// charset names are case-sensitive

							boolean utf8mb4Supported = versionMeetsMinimum(5, 5, 2);
							boolean useutf8mb4 = false;
							
							if (utf8mb4Supported) {
								useutf8mb4 = (this.io.serverCharsetIndex == 45);
							}
							
							if (!getUseOldUTF8Behavior()) {
								if (dontCheckServerMatch || !characterSetNamesMatches("utf8") 
										|| (utf8mb4Supported && !characterSetNamesMatches("utf8mb4"))) {
									execSQL(null, "SET NAMES " + (useutf8mb4 ? "utf8mb4" : "utf8"), -1, null,
											DEFAULT_RESULT_SET_TYPE,
											DEFAULT_RESULT_SET_CONCURRENCY,
											false, this.database, null, false);
								}
							} else {
								execSQL(null, "SET NAMES latin1", -1, null,
										DEFAULT_RESULT_SET_TYPE,
										DEFAULT_RESULT_SET_CONCURRENCY,
										false, this.database, null, false);
							}

							setEncoding(realJavaEncoding);
						} /* not utf-8 */else {
							String mysqlEncodingName = CharsetMapping
									.getMysqlEncodingForJavaEncoding(
											realJavaEncoding
													.toUpperCase(Locale.ENGLISH),
											this);

							/*
							 * if ("koi8_ru".equals(mysqlEncodingName)) { //
							 * This has a _different_ name in 4.1...
							 * mysqlEncodingName = "ko18r"; } else if
							 * ("euc_kr".equals(mysqlEncodingName)) { //
							 * Different name in 4.1 mysqlEncodingName =
							 * "euckr"; }
							 */

							if (mysqlEncodingName != null) {
								
								if (dontCheckServerMatch || !characterSetNamesMatches(mysqlEncodingName)) {
									execSQL(null, "SET NAMES " + mysqlEncodingName,
										-1, null,
										DEFAULT_RESULT_SET_TYPE,
										DEFAULT_RESULT_SET_CONCURRENCY,
										false, this.database, null, false);
								}
							}

							// Switch driver's encoding now, since the server
							// knows what we're sending...
							//
							setEncoding(realJavaEncoding);
						}
					} else if (getEncoding() != null) {
						// Tell the server we'll use the server default charset
						// to send our
						// queries from now on....
						String mysqlEncodingName = CharsetMapping
								.getMysqlEncodingForJavaEncoding(getEncoding()
										.toUpperCase(Locale.ENGLISH), this);
						
						if(getUseOldUTF8Behavior()){
							mysqlEncodingName = "latin1";
						}

						if (dontCheckServerMatch || !characterSetNamesMatches(mysqlEncodingName)) {
							execSQL(null, "SET NAMES " + mysqlEncodingName, -1,
								null, DEFAULT_RESULT_SET_TYPE,
								DEFAULT_RESULT_SET_CONCURRENCY, false,
								this.database, null, false);
						}

						realJavaEncoding = getEncoding();
					}

				}

				//
				// We know how to deal with any charset coming back from
				// the database, so tell the server not to do conversion
				// if the user hasn't 'forced' a result-set character set
				//

				String onServer = null;
				boolean isNullOnServer = false;
				
				if (this.serverVariables != null) {
					onServer = this.serverVariables.get("character_set_results");
					
					isNullOnServer = onServer == null || "NULL".equalsIgnoreCase(onServer) || onServer.length() == 0;
				}
				
				if (getCharacterSetResults() == null) {
					
					//
					// Only send if needed, if we're caching server variables
					// we -have- to send, because we don't know what it was
					// before we cached them.
					//
					if (!isNullOnServer) {
						execSQL(null, "SET character_set_results = NULL", -1, null,
								DEFAULT_RESULT_SET_TYPE,
								DEFAULT_RESULT_SET_CONCURRENCY, false,
								this.database, null, 
								false);
						if (!this.usingCachedConfig) {
							this.serverVariables.put(JDBC_LOCAL_CHARACTER_SET_RESULTS, null);
						}
					} else {
						if (!this.usingCachedConfig) {
							this.serverVariables.put(JDBC_LOCAL_CHARACTER_SET_RESULTS, onServer);
						}
					}
				} else {

					if(getUseOldUTF8Behavior()){
						execSQL(null, "SET NAMES " + "latin1", -1,
							null, DEFAULT_RESULT_SET_TYPE,
							DEFAULT_RESULT_SET_CONCURRENCY, false,
							this.database, null, false);
					}
					String charsetResults = getCharacterSetResults();
					String mysqlEncodingName = null;

					if ("UTF-8".equalsIgnoreCase(charsetResults)
							|| "UTF8".equalsIgnoreCase(charsetResults)) {
						mysqlEncodingName = "utf8";
					} else {
						mysqlEncodingName = CharsetMapping
								.getMysqlEncodingForJavaEncoding(charsetResults
										.toUpperCase(Locale.ENGLISH), this);
					}

					//
					// Only change the value if needed
					//
					
					if (!mysqlEncodingName.equalsIgnoreCase(
							this.serverVariables.get("character_set_results"))) {
						StringBuffer setBuf = new StringBuffer(
								"SET character_set_results = ".length()
										+ mysqlEncodingName.length());
						setBuf.append("SET character_set_results = ").append(
								mysqlEncodingName);
	
						execSQL(null, setBuf.toString(), -1, null,
								DEFAULT_RESULT_SET_TYPE,
								DEFAULT_RESULT_SET_CONCURRENCY, false,
								this.database, null, false);
						
						if (!this.usingCachedConfig) {
							this.serverVariables.put(JDBC_LOCAL_CHARACTER_SET_RESULTS, 
								mysqlEncodingName);
						}
					} else {
						if (!this.usingCachedConfig) {
							this.serverVariables.put(JDBC_LOCAL_CHARACTER_SET_RESULTS, onServer);
						}
					}
				}

				if (getConnectionCollation() != null) {
					StringBuffer setBuf = new StringBuffer(
							"SET collation_connection = ".length()
									+ getConnectionCollation().length());
					setBuf.append("SET collation_connection = ").append(
							getConnectionCollation());

					execSQL(null, setBuf.toString(), -1, null,
							DEFAULT_RESULT_SET_TYPE,
							DEFAULT_RESULT_SET_CONCURRENCY, false,
							this.database, null, false);
				}
			} else {
				// Use what the server has specified
				realJavaEncoding = getEncoding(); // so we don't get
				// swapped out in the finally
				// block....
			}
		} finally {
			// Failsafe, make sure that the driver's notion of character
			// encoding matches what the user has specified.
			//
			setEncoding(realJavaEncoding);
		}
		
		/**
		 * Check if we need a CharsetEncoder for escaping codepoints that are
		 * transformed to backslash (0x5c) in the connection encoding.
		 */
		try {
			CharsetEncoder enc = Charset.forName(getEncoding()).newEncoder();
			CharBuffer cbuf = CharBuffer.allocate(1);
			ByteBuffer bbuf = ByteBuffer.allocate(1);

			cbuf.put("\u00a5");
			cbuf.position(0);
			enc.encode(cbuf, bbuf, true);
			if(bbuf.get(0) == '\\') {
				requiresEscapingEncoder = true;
			} else {
				cbuf.clear();
				bbuf.clear();
				
				cbuf.put("\u20a9");
				cbuf.position(0);
				enc.encode(cbuf, bbuf, true);
				if(bbuf.get(0) == '\\') {
					requiresEscapingEncoder = true;
				}
			}
		} catch(java.nio.charset.UnsupportedCharsetException ucex) {
			// fallback to String API - for Java 1.4
			try {
				byte bbuf[] = StringUtils.getBytes("\u00a5", getEncoding());
				if (bbuf[0] == '\\') {
					requiresEscapingEncoder = true;
				} else {
					bbuf = StringUtils.getBytes("\u20a9", getEncoding());
					if (bbuf[0] == '\\') {
						requiresEscapingEncoder = true;
					}
				}
			} catch(UnsupportedEncodingException ueex) {
				throw SQLError.createSQLException("Unable to use encoding: " + getEncoding(),
						SQLError.SQL_STATE_GENERAL_ERROR, ueex,
						getExceptionInterceptor());
			}
		}

		return characterSetAlreadyConfigured;
	}

	/**
	 * Configures the client's timezone if required.
	 * 
	 * @throws SQLException
	 *             if the timezone the server is configured to use can't be
	 *             mapped to a Java timezone.
	 */
	private void configureTimezone() throws SQLException {
		String configuredTimeZoneOnServer = this.serverVariables.get("timezone");

		if (configuredTimeZoneOnServer == null) {
			configuredTimeZoneOnServer = this.serverVariables.get("time_zone");

			if ("SYSTEM".equalsIgnoreCase(configuredTimeZoneOnServer)) {
				configuredTimeZoneOnServer = this.serverVariables.get("system_time_zone");
			}
		}

		String canoncicalTimezone = getServerTimezone();
		
		if ((getUseTimezone() || !getUseLegacyDatetimeCode()) && configuredTimeZoneOnServer != null) {
			// user can override this with driver properties, so don't detect if that's the case
			if (canoncicalTimezone == null || StringUtils.isEmptyOrWhitespaceOnly(canoncicalTimezone)) {
				try {
					canoncicalTimezone = TimeUtil
							.getCanoncialTimezone(configuredTimeZoneOnServer, getExceptionInterceptor());

					if (canoncicalTimezone == null) {
						throw SQLError.createSQLException("Can't map timezone '"
								+ configuredTimeZoneOnServer + "' to "
								+ " canonical timezone.",
								SQLError.SQL_STATE_ILLEGAL_ARGUMENT, getExceptionInterceptor());
					}
				} catch (IllegalArgumentException iae) {
					throw SQLError.createSQLException(iae.getMessage(),
							SQLError.SQL_STATE_GENERAL_ERROR, getExceptionInterceptor());
				}
			}
		} else {
			canoncicalTimezone = getServerTimezone();
		}
		
		if (canoncicalTimezone != null && canoncicalTimezone.length() > 0) {
				this.serverTimezoneTZ = TimeZone.getTimeZone(canoncicalTimezone);

			//
			// The Calendar class has the behavior of mapping
			// unknown timezones to 'GMT' instead of throwing an
			// exception, so we must check for this...
			//
			if (!canoncicalTimezone.equalsIgnoreCase("GMT")
					&& this.serverTimezoneTZ.getID().equals("GMT")) {
				throw SQLError.createSQLException("No timezone mapping entry for '"
						+ canoncicalTimezone + "'",
						SQLError.SQL_STATE_ILLEGAL_ARGUMENT, getExceptionInterceptor());
			}

			if ("GMT".equalsIgnoreCase(this.serverTimezoneTZ.getID())) {
				this.isServerTzUTC = true;
			} else {
				this.isServerTzUTC = false;
			}
		}
	}

	private void createInitialHistogram(long[] breakpoints,
			long lowerBound, long upperBound) {

		double bucketSize = (((double) upperBound - (double) lowerBound) / HISTOGRAM_BUCKETS) * 1.25;

		if (bucketSize < 1) {
			bucketSize = 1;
		}

		for (int i = 0; i < HISTOGRAM_BUCKETS; i++) {
			breakpoints[i] = lowerBound;
			lowerBound += bucketSize;
		}
	}

	/**
	 * Creates an IO channel to the server
	 * 
	 * @param isForReconnect
	 *            is this request for a re-connect
	 * @return a new MysqlIO instance connected to a server
	 * @throws SQLException
	 *             if a database access error occurs
	 * @throws CommunicationsException
	 *             DOCUMENT ME!
	 */
	public synchronized void createNewIO(boolean isForReconnect)
			throws SQLException {
		// Synchronization Not needed for *new* connections, but defintely for
		// connections going through fail-over, since we might get the
		// new connection up and running *enough* to start sending
		// cached or still-open server-side prepared statements over
		// to the backend before we get a chance to re-prepare them...
		

		Properties mergedProps  = exposeAsProperties(this.props);

		if (!getHighAvailability()) {
			connectOneTryOnly(isForReconnect, mergedProps);
			
			return;
		} 

		connectWithRetries(isForReconnect, mergedProps);
		
	}

	private void connectWithRetries(boolean isForReconnect,
			Properties mergedProps) throws SQLException {
		double timeout = getInitialTimeout();
		boolean connectionGood = false;

		Exception connectionException = null;

		for (int attemptCount = 0; (attemptCount < getMaxReconnects())
				&& !connectionGood; attemptCount++) {
			try {
				if (this.io != null) {
					this.io.forceClose();
				}

				coreConnect(mergedProps);
				pingInternal(false, 0);
				
				boolean oldAutoCommit;
				int oldIsolationLevel;
				boolean oldReadOnly;
				String oldCatalog;
				
				synchronized (this) {
					this.connectionId = this.io.getThreadId();
					this.isClosed = false;

					// save state from old connection
					oldAutoCommit = getAutoCommit();
					oldIsolationLevel = this.isolationLevel;
					oldReadOnly = isReadOnly();
					oldCatalog = getCatalog();
	
					this.io.setStatementInterceptors(this.statementInterceptors);
				}
				
				// Server properties might be different
				// from previous connection, so initialize
				// again...
				initializePropsFromServer();

				if (isForReconnect) {
					// Restore state from old connection
					setAutoCommit(oldAutoCommit);

					if (this.hasIsolationLevels) {
						setTransactionIsolation(oldIsolationLevel);
					}

					setCatalog(oldCatalog);
					setReadOnly(oldReadOnly);
				}

				connectionGood = true;

				break;
			} catch (Exception EEE) {
				connectionException = EEE;
				connectionGood = false;
			}

				if (connectionGood) {
					break;
				}

				if (attemptCount > 0) {
					try {
						Thread.sleep((long) timeout * 1000);
					} catch (InterruptedException IE) {
						// ignore
					}
				}
			} // end attempts for a single host

		if (!connectionGood) {
			// We've really failed!
			SQLException chainedEx = SQLError.createSQLException(
					Messages.getString("Connection.UnableToConnectWithRetries",
							new Object[] {Integer.valueOf(getMaxReconnects())}),
					SQLError.SQL_STATE_UNABLE_TO_CONNECT_TO_DATASOURCE, getExceptionInterceptor());
			chainedEx.initCause(connectionException);
			
			throw chainedEx;
		}

		if (getParanoid() && !getHighAvailability()) {
			this.password = null;
			this.user = null;
		}

		if (isForReconnect) {
			//
			// Retrieve any 'lost' prepared statements if re-connecting
			//
			Iterator<Statement> statementIter = this.openStatements.values().iterator();

			//
			// We build a list of these outside the map of open statements,
			// because
			// in the process of re-preparing, we might end up having to
			// close
			// a prepared statement, thus removing it from the map, and
			// generating
			// a ConcurrentModificationException
			//
			Stack<Statement> serverPreparedStatements = null;

			while (statementIter.hasNext()) {
				Statement statementObj = statementIter.next();

				if (statementObj instanceof ServerPreparedStatement) {
					if (serverPreparedStatements == null) {
						serverPreparedStatements = new Stack<Statement>();
					}

					serverPreparedStatements.add(statementObj);
				}
			}

			if (serverPreparedStatements != null) {
				while (!serverPreparedStatements.isEmpty()) {
					((ServerPreparedStatement) serverPreparedStatements
							.pop()).rePrepare();
				}
			}
		}
	}

	private void coreConnect(Properties mergedProps) throws SQLException,
			IOException {
		int newPort = 3306;
		String newHost = "localhost";
		
		String protocol = mergedProps.getProperty(NonRegisteringDriver.PROTOCOL_PROPERTY_KEY);
		
		if (protocol != null) {
			// "new" style URL

			if ("tcp".equalsIgnoreCase(protocol)) {
				newHost = normalizeHost(mergedProps.getProperty(NonRegisteringDriver.HOST_PROPERTY_KEY));
				newPort = parsePortNumber(mergedProps.getProperty(NonRegisteringDriver.PORT_PROPERTY_KEY, "3306"));
			} else if ("pipe".equalsIgnoreCase(protocol)) {
				setSocketFactoryClassName(NamedPipeSocketFactory.class.getName());
				
				String path = mergedProps.getProperty(NonRegisteringDriver.PATH_PROPERTY_KEY);
				
				if (path != null) {
					mergedProps.setProperty(NamedPipeSocketFactory.NAMED_PIPE_PROP_NAME, path);
				}
			} else {
				// normalize for all unknown protocols
				newHost = normalizeHost(mergedProps.getProperty(NonRegisteringDriver.HOST_PROPERTY_KEY));
				newPort = parsePortNumber(mergedProps.getProperty(NonRegisteringDriver.PORT_PROPERTY_KEY, "3306"));
			}
		} else {
		
			String[] parsedHostPortPair = NonRegisteringDriver
					.parseHostPortPair(this.hostPortPair);
			newHost = parsedHostPortPair[NonRegisteringDriver.HOST_NAME_INDEX];

			newHost = normalizeHost(newHost);

			if (parsedHostPortPair[NonRegisteringDriver.PORT_NUMBER_INDEX] != null) {
				newPort = parsePortNumber(parsedHostPortPair[NonRegisteringDriver.PORT_NUMBER_INDEX]);
			}
		}

		this.port = newPort;
		this.host = newHost;
		
		this.io = new MysqlIO(newHost, newPort,
				mergedProps, getSocketFactoryClassName(),
				getProxy(), getSocketTimeout(),
				this.largeRowSizeThreshold.getValueAsInt());
		this.io.doHandshake(this.user, this.password,
				this.database);
	}

	private String normalizeHost(String hostname) {
		if (hostname == null || StringUtils.isEmptyOrWhitespaceOnly(hostname)) {
			return "localhost";
		}
		
		return hostname;
	}
	private int parsePortNumber(String portAsString)
			throws SQLException {
		int portNumber = 3306;
		try {
			portNumber = Integer
					.parseInt(portAsString);
		} catch (NumberFormatException nfe) {
			throw SQLError.createSQLException(
					"Illegal connection port value '"
							+ portAsString
							+ "'",
					SQLError.SQL_STATE_INVALID_CONNECTION_ATTRIBUTE, getExceptionInterceptor());
		}
		return portNumber;
	}

	private void connectOneTryOnly(boolean isForReconnect,
			Properties mergedProps) throws SQLException {
		Exception connectionNotEstablishedBecause = null;

		try {
			
			coreConnect(mergedProps);
			this.connectionId = this.io.getThreadId();
			this.isClosed = false;

			// save state from old connection
			boolean oldAutoCommit = getAutoCommit();
			int oldIsolationLevel = this.isolationLevel;
			boolean oldReadOnly = isReadOnly();
			String oldCatalog = getCatalog();

			this.io.setStatementInterceptors(this.statementInterceptors);
			
			// Server properties might be different
			// from previous connection, so initialize
			// again...
			initializePropsFromServer();

			if (isForReconnect) {
				// Restore state from old connection
				setAutoCommit(oldAutoCommit);

				if (this.hasIsolationLevels) {
					setTransactionIsolation(oldIsolationLevel);
				}

				setCatalog(oldCatalog);
				
				setReadOnly(oldReadOnly);
			}
			return;
			
		} catch (Exception EEE) {
			if (this.io != null) {
				this.io.forceClose();
			}

			connectionNotEstablishedBecause = EEE;

			if (EEE instanceof SQLException) {
				throw (SQLException)EEE;
			}
			
			SQLException chainedEx = SQLError.createSQLException(
					Messages.getString("Connection.UnableToConnect"),
					SQLError.SQL_STATE_UNABLE_TO_CONNECT_TO_DATASOURCE, getExceptionInterceptor());
			chainedEx.initCause(connectionNotEstablishedBecause);
			
			throw chainedEx;
		}
	}

	private synchronized void createPreparedStatementCaches() {
		int cacheSize = getPreparedStatementCacheSize();
		
		this.cachedPreparedStatementParams = new HashMap<Object, Object>(cacheSize);
		
		if (getUseServerPreparedStmts()) {
			this.serverSideStatementCheckCache = new LRUCache(cacheSize);
			
			this.serverSideStatementCache = new LRUCache(cacheSize) {
				protected boolean removeEldestEntry(java.util.Map.Entry<Object, Object> eldest) {
					if (this.maxElements <= 1) {
						return false;
					}
					
					boolean removeIt = super.removeEldestEntry(eldest);
					
					if (removeIt) {
						ServerPreparedStatement ps = 
							(ServerPreparedStatement)eldest.getValue();
						ps.isCached = false;
						ps.setClosed(false);
						
						try {
							ps.close();
						} catch (SQLException sqlEx) {
							// punt
						}
					}
					
					return removeIt;
				}
			};
		}
	}

	/**
	 * SQL statements without parameters are normally executed using Statement
	 * objects. If the same SQL statement is executed many times, it is more
	 * efficient to use a PreparedStatement
	 * 
	 * @return a new Statement object
	 * @throws SQLException
	 *             passed through from the constructor
	 */
	public java.sql.Statement createStatement() throws SQLException {
		return createStatement(DEFAULT_RESULT_SET_TYPE,
				DEFAULT_RESULT_SET_CONCURRENCY);
	}

	/**
	 * JDBC 2.0 Same as createStatement() above, but allows the default result
	 * set type and result set concurrency type to be overridden.
	 * 
	 * @param resultSetType
	 *            a result set type, see ResultSet.TYPE_XXX
	 * @param resultSetConcurrency
	 *            a concurrency type, see ResultSet.CONCUR_XXX
	 * @return a new Statement object
	 * @exception SQLException
	 *                if a database-access error occurs.
	 */
	public java.sql.Statement createStatement(int resultSetType,
			int resultSetConcurrency) throws SQLException {
		checkClosed();

		StatementImpl stmt = new StatementImpl(getLoadBalanceSafeProxy(), this.database);
		stmt.setResultSetType(resultSetType);
		stmt.setResultSetConcurrency(resultSetConcurrency);

		return stmt;
	}

	/**
	 * @see Connection#createStatement(int, int, int)
	 */
	public java.sql.Statement createStatement(int resultSetType,
			int resultSetConcurrency, int resultSetHoldability)
			throws SQLException {
		if (getPedantic()) {
			if (resultSetHoldability != java.sql.ResultSet.HOLD_CURSORS_OVER_COMMIT) {
				throw SQLError.createSQLException(
						"HOLD_CUSRORS_OVER_COMMIT is only supported holdability level",
						SQLError.SQL_STATE_ILLEGAL_ARGUMENT, getExceptionInterceptor());
			}
		}

		return createStatement(resultSetType, resultSetConcurrency);
	}

	public void dumpTestcaseQuery(String query) {
		System.err.println(query);
	}

	public Connection duplicate() throws SQLException {
		return new ConnectionImpl(	this.origHostToConnectTo, 
				this.origPortToConnectTo,
				this.props,
				this.origDatabaseToConnectTo,
				this.myURL);
	}

	/**
	 * Send a query to the server. Returns one of the ResultSet objects. This is
	 * synchronized, so Statement's queries will be serialized.
	 * 
	 * @param callingStatement
	 *            DOCUMENT ME!
	 * @param sql
	 *            the SQL statement to be executed
	 * @param maxRows
	 *            DOCUMENT ME!
	 * @param packet
	 *            DOCUMENT ME!
	 * @param resultSetType
	 *            DOCUMENT ME!
	 * @param resultSetConcurrency
	 *            DOCUMENT ME!
	 * @param streamResults
	 *            DOCUMENT ME!
	 * @param queryIsSelectOnly
	 *            DOCUMENT ME!
	 * @param catalog
	 *            DOCUMENT ME!
	 * @param unpackFields
	 *            DOCUMENT ME!
	 * @return a ResultSet holding the results
	 * @exception SQLException
	 *                if a database error occurs
	 */

	// ResultSet execSQL(Statement callingStatement, String sql,
	// int maxRowsToRetreive, String catalog) throws SQLException {
	// return execSQL(callingStatement, sql, maxRowsToRetreive, null,
	// java.sql.ResultSet.TYPE_FORWARD_ONLY,
	// DEFAULT_RESULT_SET_CONCURRENCY, catalog);
	// }
	// ResultSet execSQL(Statement callingStatement, String sql, int maxRows,
	// int resultSetType, int resultSetConcurrency, boolean streamResults,
	// boolean queryIsSelectOnly, String catalog, boolean unpackFields) throws
	// SQLException {
	// return execSQL(callingStatement, sql, maxRows, null, resultSetType,
	// resultSetConcurrency, streamResults, queryIsSelectOnly, catalog,
	// unpackFields);
	// }
	public ResultSetInternalMethods execSQL(StatementImpl callingStatement, String sql, int maxRows,
			Buffer packet, int resultSetType, int resultSetConcurrency,
			boolean streamResults, String catalog,
			Field[] cachedMetadata) throws SQLException {
		return execSQL(callingStatement, sql, maxRows, packet, resultSetType,
				resultSetConcurrency, streamResults,
				catalog, cachedMetadata, false);
	}

	public synchronized ResultSetInternalMethods execSQL(StatementImpl callingStatement, String sql, int maxRows,
			Buffer packet, int resultSetType, int resultSetConcurrency,
			boolean streamResults, String catalog,
			Field[] cachedMetadata,
			boolean isBatch) throws SQLException {
		//
		// Fall-back if the master is back online if we've
		// issued queriesBeforeRetryMaster queries since
		// we failed over
		//

		long queryStartTime = 0;

		int endOfQueryPacketPosition = 0;

		if (packet != null) {
			endOfQueryPacketPosition = packet.getPosition();
		}

		if (getGatherPerformanceMetrics()) {
			queryStartTime = System.currentTimeMillis();
		}

		this.lastQueryFinishedTime = 0; // we're busy!

		if ((getHighAvailability())
				&& (this.autoCommit || getAutoReconnectForPools())
				&& this.needsPing && !isBatch) {
			try {
				pingInternal(false, 0);

				this.needsPing = false;
			} catch (Exception Ex) {
				createNewIO(true);
			}
		}

		try {
			if (packet == null) {
				String encoding = null;

				if (getUseUnicode()) {
					encoding = getEncoding();
				}

				return this.io.sqlQueryDirect(callingStatement, sql,
						encoding, null, maxRows, resultSetType,
						resultSetConcurrency, streamResults, catalog,
						cachedMetadata);
			}

			return this.io.sqlQueryDirect(callingStatement, null, null,
					packet, maxRows, resultSetType,
					resultSetConcurrency, streamResults, catalog,
					cachedMetadata);
		} catch (java.sql.SQLException sqlE) {
			// don't clobber SQL exceptions

			if (getDumpQueriesOnException()) {
				String extractedSql = extractSqlFromPacket(sql, packet,
						endOfQueryPacketPosition);
				StringBuffer messageBuf = new StringBuffer(extractedSql
						.length() + 32);
				messageBuf
						.append("\n\nQuery being executed when exception was thrown:\n");
				messageBuf.append(extractedSql);
				messageBuf.append("\n\n");

				sqlE = appendMessageToException(sqlE, messageBuf.toString(), getExceptionInterceptor());
			}

			if ((getHighAvailability())) {
				this.needsPing = true;
			} else {
				String sqlState = sqlE.getSQLState();

				if ((sqlState != null)
						&& sqlState
								.equals(SQLError.SQL_STATE_COMMUNICATION_LINK_FAILURE)) {
					cleanup(sqlE);
				}
			}

			throw sqlE;
		} catch (Exception ex) {
			if (getHighAvailability()) {
				this.needsPing = true;
			} else if (ex instanceof IOException) {
				cleanup(ex);
			}

			SQLException sqlEx = SQLError.createSQLException(
					Messages.getString("Connection.UnexpectedException"),
					SQLError.SQL_STATE_GENERAL_ERROR, getExceptionInterceptor());
			sqlEx.initCause(ex);
			
			throw sqlEx;
		} finally {
			if (getMaintainTimeStats()) {
				this.lastQueryFinishedTime = System.currentTimeMillis();
			}


			if (getGatherPerformanceMetrics()) {
				long queryTime = System.currentTimeMillis()
						- queryStartTime;

				registerQueryExecutionTime(queryTime);
			}
		}
	}

	public String extractSqlFromPacket(String possibleSqlQuery,
			Buffer queryPacket, int endOfQueryPacketPosition)
			throws SQLException {

		String extractedSql = null;

		if (possibleSqlQuery != null) {
			if (possibleSqlQuery.length() > getMaxQuerySizeToLog()) {
				StringBuffer truncatedQueryBuf = new StringBuffer(
						possibleSqlQuery.substring(0, getMaxQuerySizeToLog()));
				truncatedQueryBuf.append(Messages.getString("MysqlIO.25"));
				extractedSql = truncatedQueryBuf.toString();
			} else {
				extractedSql = possibleSqlQuery;
			}
		}

		if (extractedSql == null) {
			// This is probably from a client-side prepared
			// statement

			int extractPosition = endOfQueryPacketPosition;

			boolean truncated = false;

			if (endOfQueryPacketPosition > getMaxQuerySizeToLog()) {
				extractPosition = getMaxQuerySizeToLog();
				truncated = true;
			}

			extractedSql = StringUtils.toString(queryPacket.getByteBuffer(), 5,
					(extractPosition - 5));

			if (truncated) {
				extractedSql += Messages.getString("MysqlIO.25"); //$NON-NLS-1$
			}
		}

		return extractedSql;

	}

	protected void finalize() throws Throwable {
		cleanup(null);
		
		super.finalize();
	}

	public StringBuffer generateConnectionCommentBlock(StringBuffer buf) {
		buf.append("/* conn id ");
		buf.append(getId());
		buf.append(" clock: ");
		buf.append(System.currentTimeMillis());
		buf.append(" */ ");

		return buf;
	}

	public int getActiveStatementCount() {
		// Might not have one of these if
		// not tracking open resources
		if (this.openStatements != null) {
			synchronized (this.openStatements) {
				return this.openStatements.size();
			}
		}

		return 0;
	}

	/**
	 * Gets the current auto-commit state
	 * 
	 * @return Current state of auto-commit
	 * @exception SQLException
	 *                if an error occurs
	 * @see setAutoCommit
	 */
	public synchronized boolean getAutoCommit() throws SQLException {
		return this.autoCommit;
	}

	/**
	 * Optimization to only use one calendar per-session, or calculate it for
	 * each call, depending on user configuration
	 */
	public Calendar getCalendarInstanceForSessionOrNew() {
		if (getDynamicCalendars()) {
			return Calendar.getInstance();
		}

		return getSessionLockedCalendar();
	}

	/**
	 * Return the connections current catalog name, or null if no catalog name
	 * is set, or we dont support catalogs.
	 * <p>
	 * <b>Note:</b> MySQL's notion of catalogs are individual databases.
	 * </p>
	 * 
	 * @return the current catalog name or null
	 * @exception SQLException
	 *                if a database access error occurs
	 */
	public synchronized String getCatalog() throws SQLException {
		return this.database;
	}

	/**
	 * @return Returns the characterSetMetadata.
	 */
	public synchronized String getCharacterSetMetadata() {
		return this.characterSetMetadata;
	}

	/**
	 * Returns the locally mapped instance of a charset converter (to avoid
	 * overhead of static synchronization).
	 * 
	 * @param javaEncodingName
	 *            the encoding name to retrieve
	 * @return a character converter, or null if one couldn't be mapped.
	 */
	public SingleByteCharsetConverter getCharsetConverter(
			String javaEncodingName) throws SQLException {
		if (javaEncodingName == null) {
			return null;
		}

		if (this.usePlatformCharsetConverters) {
			return null; // we'll use Java's built-in routines for this
			             // they're finally fast enough
		}
		
		SingleByteCharsetConverter converter = null;
		
		synchronized (this.charsetConverterMap) {
			Object asObject = this.charsetConverterMap
			.get(javaEncodingName);

			if (asObject == CHARSET_CONVERTER_NOT_AVAILABLE_MARKER) {
				return null;
			}
			
			converter = (SingleByteCharsetConverter)asObject;
			
			if (converter == null) {
				try {
					converter = SingleByteCharsetConverter.getInstance(
							javaEncodingName, this);

					if (converter == null) {
						this.charsetConverterMap.put(javaEncodingName,
								CHARSET_CONVERTER_NOT_AVAILABLE_MARKER);
					} else {
						this.charsetConverterMap.put(javaEncodingName, converter);
					}
				} catch (UnsupportedEncodingException unsupEncEx) {
					this.charsetConverterMap.put(javaEncodingName,
							CHARSET_CONVERTER_NOT_AVAILABLE_MARKER);

					converter = null;
				}
			}
		}

		return converter;
	}

	/**
	 * Returns the Java character encoding name for the given MySQL server
	 * charset index
	 * 
	 * @param charsetIndex
	 * @return the Java character encoding name for the given MySQL server
	 *         charset index
	 * @throws SQLException
	 *             if the character set index isn't known by the driver
	 */
	public String getCharsetNameForIndex(int charsetIndex)
			throws SQLException {
		String charsetName = null;

		if (getUseOldUTF8Behavior()) {
			return getEncoding();
		}

		if (charsetIndex != MysqlDefs.NO_CHARSET_INFO) {
			try {
				charsetName = this.indexToJavaCharset.get(charsetIndex);
				// checking against static maps if no custom charset found
				if (charsetName==null) charsetName = CharsetMapping.INDEX_TO_CHARSET[charsetIndex];

				if ("sjis".equalsIgnoreCase(charsetName) || 
						"MS932".equalsIgnoreCase(charsetName) /* for JDK6 */) {
					// Use our encoding so that code pages like Cp932 work
					if (CharsetMapping.isAliasForSjis(getEncoding())) {
						charsetName = getEncoding();
					}
				}
			} catch (ArrayIndexOutOfBoundsException outOfBoundsEx) {
				throw SQLError.createSQLException(
						"Unknown character set index for field '"
								+ charsetIndex + "' received from server.",
						SQLError.SQL_STATE_GENERAL_ERROR, getExceptionInterceptor());
			} catch (RuntimeException ex) {
				SQLException sqlEx = SQLError.createSQLException(ex.toString(), SQLError.SQL_STATE_ILLEGAL_ARGUMENT, null);
				sqlEx.initCause(ex);
				throw sqlEx;
			}

			// Punt
			if (charsetName == null) {
				charsetName = getEncoding();
			}
		} else {
			charsetName = getEncoding();
		}

		return charsetName;
	}

	/**
	 * DOCUMENT ME!
	 * 
	 * @return Returns the defaultTimeZone.
	 */
	public TimeZone getDefaultTimeZone() {
		return this.defaultTimeZone;
	}

	public String getErrorMessageEncoding() {
		return errorMessageEncoding;
	}

	/**
	 * @see Connection#getHoldability()
	 */
	public int getHoldability() throws SQLException {
		return java.sql.ResultSet.CLOSE_CURSORS_AT_COMMIT;
	}

	public long getId() {
		return this.connectionId;
	}

	/**
	 * NOT JDBC-Compliant, but clients can use this method to determine how long
	 * this connection has been idle. This time (reported in milliseconds) is
	 * updated once a query has completed.
	 * 
	 * @return number of ms that this connection has been idle, 0 if the driver
	 *         is busy retrieving results.
	 */
	public synchronized long getIdleFor() {
		if (this.lastQueryFinishedTime == 0) {
			return 0;
		}

		long now = System.currentTimeMillis();
		long idleTime = now - this.lastQueryFinishedTime;

		return idleTime;
	}

	/**
	 * Returns the IO channel to the server
	 * 
	 * @return the IO channel to the server
	 * @throws SQLException
	 *             if the connection is closed.
	 */
	public MysqlIO getIO() throws SQLException {
		if ((this.io == null) || this.isClosed) {
			throw SQLError.createSQLException(
					"Operation not allowed on closed connection",
					SQLError.SQL_STATE_CONNECTION_NOT_OPEN, getExceptionInterceptor());
		}

		return this.io;
	}

	/**
	 * Returns the log mechanism that should be used to log information from/for
	 * this Connection.
	 * 
	 * @return the Log instance to use for logging messages.
	 * @throws SQLException
	 *             if an error occurs
	 */
	public Log getLog() throws SQLException {
		return this.log;
	}

	public int getMaxBytesPerChar(String javaCharsetName) throws SQLException {
		return getMaxBytesPerChar(null, javaCharsetName);
	}
	
	public int getMaxBytesPerChar(Integer charsetIndex, String javaCharsetName) throws SQLException {
		
		String charset = null;
		
		try {
			// if we can get it by charsetIndex just doing it

			// getting charset name from dynamic maps in connection;
			// we do it before checking against static maps because custom charset on server
			// can be mapped to index from our static map key's diapason 
			charset = this.indexToCustomMysqlCharset.get(charsetIndex);
			// checking against static maps if no custom charset found
			if (charset==null) charset = CharsetMapping.STATIC_INDEX_TO_MYSQL_CHARSET_MAP.get(charsetIndex);

			// if we didn't find charset name by index
			if (charset == null) {
				charset = CharsetMapping.getMysqlEncodingForJavaEncoding(javaCharsetName, this);
				if ((this.io.serverCharsetIndex == 33) && (versionMeetsMinimum(5, 5, 3)) && (javaCharsetName.equalsIgnoreCase("UTF-8"))) {
					//Avoid UTF8mb4
					charset = "utf8";
				}
			}
	
			// checking against dynamic maps in connection
			Integer mblen = this.mysqlCharsetToCustomMblen.get(charset);

			// checking against static maps
			if (mblen == null) mblen = CharsetMapping.STATIC_CHARSET_TO_NUM_BYTES_MAP.get(charset);
			if (mblen == null) mblen = CharsetMapping.STATIC_4_0_CHARSET_TO_NUM_BYTES_MAP.get(charset);
	
			if (mblen != null) return mblen.intValue();
		} catch (SQLException ex) {
			throw ex;
		} catch (RuntimeException ex) {
			SQLException sqlEx = SQLError.createSQLException(ex.toString(), SQLError.SQL_STATE_ILLEGAL_ARGUMENT, null);
			sqlEx.initCause(ex);
			throw sqlEx;
		}

		return 1; // we don't know
	}

	/**
	 * A connection's database is able to provide information describing its
	 * tables, its supported SQL grammar, its stored procedures, the
	 * capabilities of this connection, etc. This information is made available
	 * through a DatabaseMetaData object.
	 * 
	 * @return a DatabaseMetaData object for this connection
	 * @exception SQLException
	 *                if a database access error occurs
	 */
	public java.sql.DatabaseMetaData getMetaData() throws SQLException {
		return getMetaData(true, true);
	}
	
	private java.sql.DatabaseMetaData getMetaData(boolean checkClosed, boolean checkForInfoSchema) throws SQLException {
		if (checkClosed) {
			checkClosed();	
		}
		
		return com.mysql.jdbc.DatabaseMetaData.getInstance(getLoadBalanceSafeProxy(), this.database, checkForInfoSchema);
	}

	public java.sql.Statement getMetadataSafeStatement() throws SQLException {
		java.sql.Statement stmt = createStatement();

		if (stmt.getMaxRows() != 0) {
			stmt.setMaxRows(0);
		}

		stmt.setEscapeProcessing(false);
		
		if (stmt.getFetchSize() != 0) {
			stmt.setFetchSize(0);
		}

		return stmt;
	}

	/**
	 * Returns the packet buffer size the MySQL server reported upon connection
	 * 
	 * @return DOCUMENT ME!
	 */
	public int getNetBufferLength() {
		return this.netBufferLength;
	}

	/**
	 * Returns the server's character set
	 * 
	 * @return the server's character set.
	 */
	public String getServerCharacterEncoding() {
		if (this.io.versionMeetsMinimum(4, 1, 0)) {
			String charset = this.indexToCustomMysqlCharset.get(this.io.serverCharsetIndex);
			if (charset == null) charset = CharsetMapping.STATIC_INDEX_TO_MYSQL_CHARSET_MAP.get(this.io.serverCharsetIndex);
			return charset != null ? charset : this.serverVariables.get("character_set_server");
		}
		return this.serverVariables.get("character_set");
	}

	public int getServerMajorVersion() {
		return this.io.getServerMajorVersion();
	}

	public int getServerMinorVersion() {
		return this.io.getServerMinorVersion();
	}

	public int getServerSubMinorVersion() {
		return this.io.getServerSubMinorVersion();
	}

	/**
	 * DOCUMENT ME!
	 * 
	 * @return DOCUMENT ME!
	 */
	public TimeZone getServerTimezoneTZ() {
		return this.serverTimezoneTZ;
	}
	
	
	public String getServerVariable(String variableName) {
		if (this.serverVariables != null) {
			return this.serverVariables.get(variableName);
		}

		return null;
	}

	public String getServerVersion() {
		return this.io.getServerVersion();
	}

	public Calendar getSessionLockedCalendar() {
	
		return this.sessionCalendar;
	}

	/**
	 * Get this Connection's current transaction isolation mode.
	 * 
	 * @return the current TRANSACTION_ mode value
	 * @exception SQLException
	 *                if a database access error occurs
	 */
	public synchronized int getTransactionIsolation() throws SQLException {

		if (this.hasIsolationLevels && !getUseLocalSessionState()) {
			java.sql.Statement stmt = null;
			java.sql.ResultSet rs = null;

			try {
				stmt = getMetadataSafeStatement();

				String query = null;

				int offset = 0;
				
				if (versionMeetsMinimum(4, 0, 3)) {
					query = "SELECT @@session.tx_isolation";
					offset = 1;
				} else {
					query = "SHOW VARIABLES LIKE 'transaction_isolation'";
					offset = 2;
				}

				rs = stmt.executeQuery(query);

				if (rs.next()) {
					String s = rs.getString(offset);

					if (s != null) {
						Integer intTI = mapTransIsolationNameToValue.get(s);

						if (intTI != null) {
							return intTI.intValue();
						}
					}

					throw SQLError.createSQLException(
							"Could not map transaction isolation '" + s
									+ " to a valid JDBC level.",
							SQLError.SQL_STATE_GENERAL_ERROR, getExceptionInterceptor());
				}

				throw SQLError.createSQLException(
						"Could not retrieve transaction isolation level from server",
						SQLError.SQL_STATE_GENERAL_ERROR, getExceptionInterceptor());

			} finally {
				if (rs != null) {
					try {
						rs.close();
					} catch (Exception ex) {
						// ignore
						;
					}

					rs = null;
				}

				if (stmt != null) {
					try {
						stmt.close();
					} catch (Exception ex) {
						// ignore
						;
					}

					stmt = null;
				}
			}
		}

		return this.isolationLevel;
	}

	/**
	 * JDBC 2.0 Get the type-map object associated with this connection. By
	 * default, the map returned is empty.
	 * 
	 * @return the type map
	 * @throws SQLException
	 *             if a database error occurs
	 */
	public synchronized java.util.Map getTypeMap() throws SQLException {
		if (this.typeMap == null) {
			this.typeMap = new HashMap();
		}

		return this.typeMap;
	}

	public String getURL() {
		return this.myURL;
	}

	public String getUser() {
		return this.user;
	}

	public Calendar getUtcCalendar() {
		return this.utcCalendar;
	}
	
	/**
	 * The first warning reported by calls on this Connection is returned.
	 * <B>Note:</B> Sebsequent warnings will be changed to this
	 * java.sql.SQLWarning
	 * 
	 * @return the first java.sql.SQLWarning or null
	 * @exception SQLException
	 *                if a database access error occurs
	 */
	public SQLWarning getWarnings() throws SQLException {
		return null;
	}

	public boolean hasSameProperties(Connection c) {
		return this.props.equals(c.getProperties());
	}

	public Properties getProperties() {
		return this.props;
	}
	
	public boolean hasTriedMaster() {
		return this.hasTriedMasterFlag;
	}

	public void incrementNumberOfPreparedExecutes() {
		if (getGatherPerformanceMetrics()) {
			this.numberOfPreparedExecutes++;

			// We need to increment this, because
			// server-side prepared statements bypass
			// any execution by the connection itself...
			this.numberOfQueriesIssued++;
		}
	}

	public void incrementNumberOfPrepares() {
		if (getGatherPerformanceMetrics()) {
			this.numberOfPrepares++;
		}
	}

	public void incrementNumberOfResultSetsCreated() {
		if (getGatherPerformanceMetrics()) {
			this.numberOfResultSetsCreated++;
		}
	}

	/**
	 * Initializes driver properties that come from URL or properties passed to
	 * the driver manager.
	 * 
	 * @param info
	 *            DOCUMENT ME!
	 * @throws SQLException
	 *             DOCUMENT ME!
	 */
	private void initializeDriverProperties(Properties info)
			throws SQLException {
		initializeProperties(info);
		
		String exceptionInterceptorClasses = getExceptionInterceptors();
		
		if (exceptionInterceptorClasses != null && !"".equals(exceptionInterceptorClasses)) {
			this.exceptionInterceptor = new ExceptionInterceptorChain(exceptionInterceptorClasses);
			this.exceptionInterceptor.init(this, info);
		}
		
		this.usePlatformCharsetConverters = getUseJvmCharsetConverters();

		this.log = LogFactory.getLogger(getLogger(), LOGGER_INSTANCE_NAME, getExceptionInterceptor());

		if (getProfileSql() || getUseUsageAdvisor()) {
			this.eventSink = ProfilerEventHandlerFactory.getInstance(getLoadBalanceSafeProxy());
		}

		if (getCachePreparedStatements()) {
			createPreparedStatementCaches();		
		}

		if (getNoDatetimeStringSync() && getUseTimezone()) {
			throw SQLError.createSQLException(
					"Can't enable noDatetimeSync and useTimezone configuration "
							+ "properties at the same time",
					SQLError.SQL_STATE_INVALID_CONNECTION_ATTRIBUTE, getExceptionInterceptor());
		}
		
		if (getCacheCallableStatements()) {
			this.parsedCallableStatementCache = new LRUCache(
					getCallableStatementCacheSize());
		}
		
		if (getAllowMultiQueries()) {
			setCacheResultSetMetadata(false); // we don't handle this yet
		}
		
		if (getCacheResultSetMetadata()) {
			this.resultSetMetadataCache = new LRUCache(
					getMetadataCacheSize());
		}
	}

	/**
	 * Sets varying properties that depend on server information. Called once we
	 * have connected to the server.
	 * 
	 * @param info
	 *            DOCUMENT ME!
	 * @throws SQLException
	 *             DOCUMENT ME!
	 */
	private void initializePropsFromServer() throws SQLException {
		String connectionInterceptorClasses = getConnectionLifecycleInterceptors();
		
		this.connectionLifecycleInterceptors = null;
		
		if (connectionInterceptorClasses != null) {
			this.connectionLifecycleInterceptors = Util.loadExtensions(this, this.props, 
					connectionInterceptorClasses, 
					"Connection.badLifecycleInterceptor", getExceptionInterceptor());
		}
		
		setSessionVariables();

		//
		// the "boolean" type didn't come along until MySQL-4.1
		//

		if (!versionMeetsMinimum(4, 1, 0)) {
			setTransformedBitIsBoolean(false);
		}

		this.parserKnowsUnicode = versionMeetsMinimum(4, 1, 0);

		//
		// Users can turn off detection of server-side prepared statements
		//
		if (getUseServerPreparedStmts() && versionMeetsMinimum(4, 1, 0)) {
			this.useServerPreparedStmts = true;

			if (versionMeetsMinimum(5, 0, 0) && !versionMeetsMinimum(5, 0, 3)) {
				this.useServerPreparedStmts = false; // 4.1.2+ style prepared
				// statements
				// don't work on these versions
			}
		}
		
		//
		// If version is greater than 3.21.22 get the server
		// variables.
		if (versionMeetsMinimum(3, 21, 22)) {
			loadServerVariables();

			if (versionMeetsMinimum(5, 0, 2)) {
				this.autoIncrementIncrement = getServerVariableAsInt("auto_increment_increment", 1);
			} else {
				this.autoIncrementIncrement = 1;
			}
			
			buildCollationMapping();

			LicenseConfiguration.checkLicenseType(this.serverVariables);

			String lowerCaseTables = this.serverVariables.get("lower_case_table_names");

			this.lowerCaseTableNames = "on".equalsIgnoreCase(lowerCaseTables)
					|| "1".equalsIgnoreCase(lowerCaseTables)
					|| "2".equalsIgnoreCase(lowerCaseTables);

			this.storesLowerCaseTableName = "1".equalsIgnoreCase(lowerCaseTables) ||
					"on".equalsIgnoreCase(lowerCaseTables);

			configureTimezone();

			if (this.serverVariables.containsKey("max_allowed_packet")) {
				int serverMaxAllowedPacket = getServerVariableAsInt("max_allowed_packet", -1);
				// use server value if maxAllowedPacket hasn't been given, or max_allowed_packet is smaller
				if (serverMaxAllowedPacket != -1 && (serverMaxAllowedPacket < getMaxAllowedPacket() ||
						getMaxAllowedPacket() <= 0))
					setMaxAllowedPacket(serverMaxAllowedPacket);
				else if (serverMaxAllowedPacket == -1 && getMaxAllowedPacket() == -1)
					setMaxAllowedPacket(65535);
				
				int preferredBlobSendChunkSize = getBlobSendChunkSize();
				
				int allowedBlobSendChunkSize = Math.min(preferredBlobSendChunkSize, 
						getMaxAllowedPacket()) - 
						ServerPreparedStatement.BLOB_STREAM_READ_BUF_SIZE 
						- 11 /* LONG_DATA and MySQLIO packet header size */;
				
				setBlobSendChunkSize(String.valueOf(allowedBlobSendChunkSize));
			}

			if (this.serverVariables.containsKey("net_buffer_length")) {
				this.netBufferLength = getServerVariableAsInt("net_buffer_length", 16 * 1024);
			}

			checkTransactionIsolationLevel();
			
			if (!versionMeetsMinimum(4, 1, 0)) {
				checkServerEncoding();
			}

			this.io.checkForCharsetMismatch();

			if (this.serverVariables.containsKey("sql_mode")) {
				int sqlMode = 0;

				String sqlModeAsString = this.serverVariables.get("sql_mode");
				try {
					sqlMode = Integer.parseInt(sqlModeAsString);
				} catch (NumberFormatException nfe) {
					// newer versions of the server has this as a string-y
					// list...
					sqlMode = 0;

					if (sqlModeAsString != null) {
						if (sqlModeAsString.indexOf("ANSI_QUOTES") != -1) {
							sqlMode |= 4;
						}

						if (sqlModeAsString.indexOf("NO_BACKSLASH_ESCAPES") != -1) {
							this.noBackslashEscapes = true;
						}
					}
				}

				if ((sqlMode & 4) > 0) {
					this.useAnsiQuotes = true;
				} else {
					this.useAnsiQuotes = false;
				}
			}
		}
		
		try {
			this.errorMessageEncoding = 
				CharsetMapping.getCharacterEncodingForErrorMessages(this);
		} catch (SQLException ex) {
			throw ex;
		} catch (RuntimeException ex) {
			SQLException sqlEx = SQLError.createSQLException(ex.toString(), SQLError.SQL_STATE_ILLEGAL_ARGUMENT, null);
			sqlEx.initCause(ex);
			throw sqlEx;
		}
		
		
		boolean overrideDefaultAutocommit = isAutoCommitNonDefaultOnServer();
	
		configureClientCharacterSet(false);

		if (versionMeetsMinimum(3, 23, 15)) {
			this.transactionsSupported = true;
			
			if (!overrideDefaultAutocommit) {
				setAutoCommit(true); // to override anything
				// the server is set to...reqd
				// by JDBC spec.
			}
		} else {
			this.transactionsSupported = false;
		}
		

		if (versionMeetsMinimum(3, 23, 36)) {
			this.hasIsolationLevels = true;
		} else {
			this.hasIsolationLevels = false;
		}

		this.hasQuotedIdentifiers = versionMeetsMinimum(3, 23, 6);

		this.io.resetMaxBuf();

		//
		// If we're using MySQL 4.1.0 or newer, we need to figure
		// out what character set metadata will be returned in,
		// and then map that to a Java encoding name.
		//
		// We've already set it, and it might be different than what
		// was originally on the server, which is why we use the
		// "special" key to retrieve it
		if (this.io.versionMeetsMinimum(4, 1, 0)) {
			String characterSetResultsOnServerMysql = this.serverVariables.get(JDBC_LOCAL_CHARACTER_SET_RESULTS);

			if (characterSetResultsOnServerMysql == null
					|| StringUtils.startsWithIgnoreCaseAndWs(
							characterSetResultsOnServerMysql, "NULL")
					|| characterSetResultsOnServerMysql.length() == 0) {
				String defaultMetadataCharsetMysql = this.serverVariables.get("character_set_system");
				String defaultMetadataCharset = null;

				if (defaultMetadataCharsetMysql != null) {
					defaultMetadataCharset = getJavaEncodingForMysqlEncoding(defaultMetadataCharsetMysql);
				} else {
					defaultMetadataCharset = "UTF-8";
				}

				this.characterSetMetadata = defaultMetadataCharset;
			} else {
				this.characterSetResultsOnServer = getJavaEncodingForMysqlEncoding(characterSetResultsOnServerMysql);
				this.characterSetMetadata = this.characterSetResultsOnServer;
			}
		} else {
			this.characterSetMetadata = getEncoding();
		}

		//
		// Query cache is broken wrt. multi-statements before MySQL-4.1.10
		//

		if (versionMeetsMinimum(4, 1, 0)
				&& !this.versionMeetsMinimum(4, 1, 10)
				&& getAllowMultiQueries()) {
			if (isQueryCacheEnabled()) {
				setAllowMultiQueries(false);
			}
		}
		
		if (versionMeetsMinimum(5, 0, 0) && 
				(getUseLocalTransactionState() || getElideSetAutoCommits()) &&
				isQueryCacheEnabled() && !versionMeetsMinimum(6, 0, 10)) {
			// Can't trust the server status flag on the wire if query cache is enabled,
			// due to Bug#36326
			setUseLocalTransactionState(false);
			setElideSetAutoCommits(false);
		}
		
		//
		// Server can do this more efficiently for us
		//
		
		setupServerForTruncationChecks();
	}

	private boolean isQueryCacheEnabled() {
		return "ON".equalsIgnoreCase(this.serverVariables.get("query_cache_type"))
				&& !"0".equalsIgnoreCase(this.serverVariables.get("query_cache_size"));
	}

	private int getServerVariableAsInt(String variableName, int fallbackValue)
			throws SQLException {
		try {
			return Integer.parseInt(this.serverVariables.get(variableName));
		} catch (NumberFormatException nfe) {
			getLog().logWarn(Messages.getString("Connection.BadValueInServerVariables", new Object[] {variableName, 
					this.serverVariables.get(variableName), Integer.valueOf(fallbackValue)}));
			
			return fallbackValue;
		}
	}

	/**
	 * Has the default autocommit value of 0 been changed on the server
	 * via init_connect?
	 * 
	 * @return true if autocommit is not the default of '0' on the server.
	 * 
	 * @throws SQLException
	 */
	private boolean isAutoCommitNonDefaultOnServer() throws SQLException {
		boolean overrideDefaultAutocommit = false;
		
		String initConnectValue = this.serverVariables.get("init_connect");

		if (versionMeetsMinimum(4, 1, 2) && initConnectValue != null
				&& initConnectValue.length() > 0) {
			if (!getElideSetAutoCommits()) {
				// auto-commit might have changed
				java.sql.ResultSet rs = null;
				java.sql.Statement stmt = null;
				
				try {
					stmt = getMetadataSafeStatement();
					
					rs = stmt.executeQuery("SELECT @@session.autocommit");
					
					if (rs.next()) {
						this.autoCommit = rs.getBoolean(1);
						if (this.autoCommit != true) {
							overrideDefaultAutocommit = true;
						}
					}
					
				} finally {
					if (rs != null) {
						try {
							rs.close();
						} catch (SQLException sqlEx) {
							// do nothing
						}
					}
					
					if (stmt != null) {
						try {
							stmt.close();
						} catch (SQLException sqlEx) {
							// do nothing
						}
					}
				}
			} else {
				if (this.getIO().isSetNeededForAutoCommitMode(true)) {
					// we're not in standard autocommit=true mode
					this.autoCommit = false;
					overrideDefaultAutocommit = true;
				}
			}
		}
		
		return overrideDefaultAutocommit;
	}

	public boolean isClientTzUTC() {
		return this.isClientTzUTC;
	}

	/**
	 * DOCUMENT ME!
	 * 
	 * @return DOCUMENT ME!
	 */
	public boolean isClosed() {
		return this.isClosed;
	}

	public boolean isCursorFetchEnabled() throws SQLException {
		return (versionMeetsMinimum(5, 0, 2) && getUseCursorFetch());
	}

	public boolean isInGlobalTx() {
		return this.isInGlobalTx;
	}

	/**
	 * Is this connection connected to the first host in the list if
	 * there is a list of servers in the URL?
	 * 
	 * @return true if this connection is connected to the first in 
	 * the list.
	 */
	public synchronized boolean isMasterConnection() {
		return false; // handled higher up
	}

	/**
	 * Is the server in a sql_mode that doesn't allow us to use \\ to escape
	 * things?
	 * 
	 * @return Returns the noBackslashEscapes.
	 */
	public boolean isNoBackslashEscapesSet() {
		return this.noBackslashEscapes;
	}

	public boolean isReadInfoMsgEnabled() {
		return this.readInfoMsg;
	}

	/**
	 * Tests to see if the connection is in Read Only Mode. Note that we cannot
	 * really put the database in read only mode, but we pretend we can by
	 * returning the value of the readOnly flag
	 * 
	 * @return true if the connection is read only
	 * @exception SQLException
	 *                if a database access error occurs
	 */
	public boolean isReadOnly() throws SQLException {
		return this.readOnly;
	}

	public boolean isRunningOnJDK13() {
		return this.isRunningOnJDK13;
	}

	public synchronized boolean isSameResource(Connection otherConnection) {
		if (otherConnection == null) {
			return false;
		}
		
		boolean directCompare = true;
		
		String otherHost = ((ConnectionImpl)otherConnection).origHostToConnectTo;
		String otherOrigDatabase = ((ConnectionImpl)otherConnection).origDatabaseToConnectTo;
		String otherCurrentCatalog = ((ConnectionImpl)otherConnection).database;
		
		if (!nullSafeCompare(otherHost, this.origHostToConnectTo)) {
			directCompare = false;
		} else if (otherHost != null && otherHost.indexOf(',') == -1 && 
				otherHost.indexOf(':') == -1) {
			// need to check port numbers
			directCompare = (((ConnectionImpl)otherConnection).origPortToConnectTo == 
				this.origPortToConnectTo);
		}
		
		if (directCompare) {
			if (!nullSafeCompare(otherOrigDatabase, this.origDatabaseToConnectTo)) {			directCompare = false;
				directCompare = false;
			} else if (!nullSafeCompare(otherCurrentCatalog, this.database)) {
				directCompare = false;
			}
		}

		if (directCompare) {
			return true;
		}
		
		// Has the user explicitly set a resourceId?
		String otherResourceId = ((ConnectionImpl)otherConnection).getResourceId();
		String myResourceId = getResourceId();
		
		if (otherResourceId != null || myResourceId != null) {
			directCompare = nullSafeCompare(otherResourceId, myResourceId);
			
			if (directCompare) {
				return true;
			}
		}
		
		return false;	
	}

	public boolean isServerTzUTC() {
		return this.isServerTzUTC;
	}

	private boolean usingCachedConfig = false;

	/**
	 * Loads the result of 'SHOW VARIABLES' into the serverVariables field so
	 * that the driver can configure itself.
	 * 
	 * @throws SQLException
	 *             if the 'SHOW VARIABLES' query fails for any reason.
	 */
	private void loadServerVariables() throws SQLException {

		if (getCacheServerConfiguration()) {
			synchronized (serverConfigByUrl) {
				Map<String, String> cachedVariableMap = serverConfigByUrl.get(getURL());

				if (cachedVariableMap != null) {
					this.serverVariables = cachedVariableMap;
					this.usingCachedConfig = true;

					return;
				}
			}
		}

		java.sql.Statement stmt = null;
		java.sql.ResultSet results = null;

		try {
			stmt = getMetadataSafeStatement();
			
			String version = this.dbmd.getDriverVersion();
			
			if (version != null && version.indexOf('*') != -1) {
				StringBuffer buf = new StringBuffer(version.length() + 10);

				for (int i = 0; i < version.length(); i++) {
					char c = version.charAt(i);

					if (c == '*') {
						buf.append("[star]");
					} else {
						buf.append(c);
					}
				}

				version = buf.toString();
			}

			String versionComment = (this.getParanoid() || version == null) ? ""
					: "/* " + version + " */";
			
			String query = versionComment + "SHOW VARIABLES";
			
			if (versionMeetsMinimum(5, 0, 3)) {
				query = versionComment + "SHOW VARIABLES WHERE Variable_name ='language'"
					+ " OR Variable_name = 'net_write_timeout'"
					+ " OR Variable_name = 'interactive_timeout'"
					+ " OR Variable_name = 'wait_timeout'"
					+ " OR Variable_name = 'character_set_client'"
					+ " OR Variable_name = 'character_set_connection'"
					+ " OR Variable_name = 'character_set'"
					+ " OR Variable_name = 'character_set_server'"
					+ " OR Variable_name = 'tx_isolation'"
					+ " OR Variable_name = 'transaction_isolation'"
					+ " OR Variable_name = 'character_set_results'"
					+ " OR Variable_name = 'timezone'"
					+ " OR Variable_name = 'time_zone'"
					+ " OR Variable_name = 'system_time_zone'"
					+ " OR Variable_name = 'lower_case_table_names'"
					+ " OR Variable_name = 'max_allowed_packet'"
					+ " OR Variable_name = 'net_buffer_length'"
					+ " OR Variable_name = 'sql_mode'"
					+ " OR Variable_name = 'query_cache_type'"
					+ " OR Variable_name = 'query_cache_size'"
					+ " OR Variable_name = 'init_connect'";
			}
			
			this.serverVariables = new HashMap<String, String>();

			results = stmt.executeQuery(query);
			
			while (results.next()) {
				this.serverVariables.put(results.getString(1), results
						.getString(2));
			}

			results.close();
			results = null;
			
			if (versionMeetsMinimum(5, 0, 2)) {
				results = stmt.executeQuery(versionComment + "SELECT @@session.auto_increment_increment");
				
				if (results.next()) {
					this.serverVariables.put("auto_increment_increment", results.getString(1));
				}
			}
			
			if (getCacheServerConfiguration()) {
				synchronized (serverConfigByUrl) {
					serverConfigByUrl.put(getURL(), this.serverVariables);
					
					this.usingCachedConfig = true;
				}
			}
		} catch (SQLException e) {
			throw e;
		} finally {
			if (results != null) {
				try {
					results.close();
				} catch (SQLException sqlE) {
					;
				}
			}

			if (stmt != null) {
				try {
					stmt.close();
				} catch (SQLException sqlE) {
					;
				}
			}
		}
	}

	private int autoIncrementIncrement = 0;
	
	public int getAutoIncrementIncrement() {
		return this.autoIncrementIncrement;
	}
	
	/**
	 * Is the server configured to use lower-case table names only?
	 * 
	 * @return true if lower_case_table_names is 'on'
	 */
	public boolean lowerCaseTableNames() {
		return this.lowerCaseTableNames;
	}

	/**
	 * Has the maxRows value changed?
	 * 
	 * @param stmt
	 *            DOCUMENT ME!
	 */
	public synchronized void maxRowsChanged(Statement stmt) {
		if (this.statementsUsingMaxRows == null) {
			this.statementsUsingMaxRows = new HashMap<Statement, Statement>();
		}

		this.statementsUsingMaxRows.put(stmt, stmt);

		this.maxRowsChanged = true;
	}

	/**
	 * A driver may convert the JDBC sql grammar into its system's native SQL
	 * grammar prior to sending it; nativeSQL returns the native form of the
	 * statement that the driver would have sent.
	 * 
	 * @param sql
	 *            a SQL statement that may contain one or more '?' parameter
	 *            placeholders
	 * @return the native form of this statement
	 * @exception SQLException
	 *                if a database access error occurs
	 */
	public String nativeSQL(String sql) throws SQLException {
		if (sql == null) {
			return null;
		}

		Object escapedSqlResult = EscapeProcessor.escapeSQL(sql,
                                                          serverSupportsConvertFn(),
                                                          getLoadBalanceSafeProxy());

		if (escapedSqlResult instanceof String) {
			return (String) escapedSqlResult;
		}

		return ((EscapeProcessorResult) escapedSqlResult).escapedSql;
	}

	private CallableStatement parseCallableStatement(String sql)
			throws SQLException {
		Object escapedSqlResult = EscapeProcessor.escapeSQL(sql,
				serverSupportsConvertFn(), getLoadBalanceSafeProxy());

		boolean isFunctionCall = false;
		String parsedSql = null;

		if (escapedSqlResult instanceof EscapeProcessorResult) {
			parsedSql = ((EscapeProcessorResult) escapedSqlResult).escapedSql;
			isFunctionCall = ((EscapeProcessorResult) escapedSqlResult).callingStoredFunction;
		} else {
			parsedSql = (String) escapedSqlResult;
			isFunctionCall = false;
		}

		return CallableStatement.getInstance(getLoadBalanceSafeProxy(), parsedSql, this.database,
				isFunctionCall);
	}

	/**
	 * DOCUMENT ME!
	 * 
	 * @return DOCUMENT ME!
	 */
	public boolean parserKnowsUnicode() {
		return this.parserKnowsUnicode;
	}

	/**
	 * Detect if the connection is still good
	 * 
	 * @throws SQLException
	 *             if the ping fails
	 */
	public void ping() throws SQLException {
		pingInternal(true, 0);
	}

	public void pingInternal(boolean checkForClosedConnection, int timeoutMillis)
			throws SQLException {
		if (checkForClosedConnection) {
			checkClosed();
		}

		long pingMillisLifetime = getSelfDestructOnPingSecondsLifetime();
		int pingMaxOperations = getSelfDestructOnPingMaxOperations();

		if ((pingMillisLifetime > 0 && (System.currentTimeMillis() - this.connectionCreationTimeMillis) > pingMillisLifetime)
				|| (pingMaxOperations > 0 && pingMaxOperations <= this.io
						.getCommandCount())) {

			close();

			throw SQLError.createSQLException(Messages
					.getString("Connection.exceededConnectionLifetime"),
					SQLError.SQL_STATE_COMMUNICATION_LINK_FAILURE, getExceptionInterceptor());
		}
		// Need MySQL-3.22.1, but who uses anything older!?
		this.io.sendCommand(MysqlDefs.PING, null, null, false, null, timeoutMillis);
	}

	/**
	 * DOCUMENT ME!
	 * 
	 * @param sql
	 *            DOCUMENT ME!
	 * @return DOCUMENT ME!
	 * @throws SQLException
	 *             DOCUMENT ME!
	 */
	public java.sql.CallableStatement prepareCall(String sql)
			throws SQLException {

		return prepareCall(sql, DEFAULT_RESULT_SET_TYPE,
				DEFAULT_RESULT_SET_CONCURRENCY);
	}

	/**
	 * JDBC 2.0 Same as prepareCall() above, but allows the default result set
	 * type and result set concurrency type to be overridden.
	 * 
	 * @param sql
	 *            the SQL representing the callable statement
	 * @param resultSetType
	 *            a result set type, see ResultSet.TYPE_XXX
	 * @param resultSetConcurrency
	 *            a concurrency type, see ResultSet.CONCUR_XXX
	 * @return a new CallableStatement object containing the pre-compiled SQL
	 *         statement
	 * @exception SQLException
	 *                if a database-access error occurs.
	 */
	public java.sql.CallableStatement prepareCall(String sql,
			int resultSetType, int resultSetConcurrency) throws SQLException {
		if (versionMeetsMinimum(5, 0, 0)) {
			CallableStatement cStmt = null;

			if (!getCacheCallableStatements()) {

				cStmt = parseCallableStatement(sql);
			} else {
				synchronized (this.parsedCallableStatementCache) {
					CompoundCacheKey key = new CompoundCacheKey(getCatalog(), sql);
	
					CallableStatement.CallableStatementParamInfo cachedParamInfo = (CallableStatement.CallableStatementParamInfo) this.parsedCallableStatementCache
							.get(key);
	
					if (cachedParamInfo != null) {
						cStmt = CallableStatement.getInstance(getLoadBalanceSafeProxy(), cachedParamInfo);
					} else {
						cStmt = parseCallableStatement(sql);
	
						synchronized (cStmt) {
							cachedParamInfo = cStmt.paramInfo;
						}
	
						this.parsedCallableStatementCache.put(key, cachedParamInfo);
					}
				}
			}

			cStmt.setResultSetType(resultSetType);
			cStmt.setResultSetConcurrency(resultSetConcurrency);

			return cStmt;
		}

		throw SQLError.createSQLException("Callable statements not " + "supported.",
				SQLError.SQL_STATE_DRIVER_NOT_CAPABLE, getExceptionInterceptor());
	}

	/**
	 * @see Connection#prepareCall(String, int, int, int)
	 */
	public java.sql.CallableStatement prepareCall(String sql,
			int resultSetType, int resultSetConcurrency,
			int resultSetHoldability) throws SQLException {
		if (getPedantic()) {
			if (resultSetHoldability != java.sql.ResultSet.HOLD_CURSORS_OVER_COMMIT) {
				throw SQLError.createSQLException(
						"HOLD_CUSRORS_OVER_COMMIT is only supported holdability level",
						SQLError.SQL_STATE_ILLEGAL_ARGUMENT, getExceptionInterceptor());
			}
		}

		CallableStatement cStmt = (com.mysql.jdbc.CallableStatement) prepareCall(
				sql, resultSetType, resultSetConcurrency);

		return cStmt;
	}

	/**
	 * A SQL statement with or without IN parameters can be pre-compiled and
	 * stored in a PreparedStatement object. This object can then be used to
	 * efficiently execute this statement multiple times.
	 * <p>
	 * <B>Note:</B> This method is optimized for handling parametric SQL
	 * statements that benefit from precompilation if the driver supports
	 * precompilation. In this case, the statement is not sent to the database
	 * until the PreparedStatement is executed. This has no direct effect on
	 * users; however it does affect which method throws certain
	 * java.sql.SQLExceptions
	 * </p>
	 * <p>
	 * MySQL does not support precompilation of statements, so they are handled
	 * by the driver.
	 * </p>
	 * 
	 * @param sql
	 *            a SQL statement that may contain one or more '?' IN parameter
	 *            placeholders
	 * @return a new PreparedStatement object containing the pre-compiled
	 *         statement.
	 * @exception SQLException
	 *                if a database access error occurs.
	 */
	public java.sql.PreparedStatement prepareStatement(String sql)
			throws SQLException {
		return prepareStatement(sql, DEFAULT_RESULT_SET_TYPE,
				DEFAULT_RESULT_SET_CONCURRENCY);
	}

	/**
	 * @see Connection#prepareStatement(String, int)
	 */
	public java.sql.PreparedStatement prepareStatement(String sql,
			int autoGenKeyIndex) throws SQLException {
		java.sql.PreparedStatement pStmt = prepareStatement(sql);

		((com.mysql.jdbc.PreparedStatement) pStmt)
				.setRetrieveGeneratedKeys(autoGenKeyIndex == java.sql.Statement.RETURN_GENERATED_KEYS);

		return pStmt;
	}

	/**
	 * JDBC 2.0 Same as prepareStatement() above, but allows the default result
	 * set type and result set concurrency type to be overridden.
	 * 
	 * @param sql
	 *            the SQL query containing place holders
	 * @param resultSetType
	 *            a result set type, see ResultSet.TYPE_XXX
	 * @param resultSetConcurrency
	 *            a concurrency type, see ResultSet.CONCUR_XXX
	 * @return a new PreparedStatement object containing the pre-compiled SQL
	 *         statement
	 * @exception SQLException
	 *                if a database-access error occurs.
	 */
	public synchronized java.sql.PreparedStatement prepareStatement(String sql,
			int resultSetType, int resultSetConcurrency) throws SQLException {
		checkClosed();

		//
		// FIXME: Create warnings if can't create results of the given
		// type or concurrency
		//
		PreparedStatement pStmt = null;
		
		boolean canServerPrepare = true;
		
		String nativeSql = getProcessEscapeCodesForPrepStmts() ? nativeSQL(sql): sql;
		
		if (this.useServerPreparedStmts && getEmulateUnsupportedPstmts()) {
			canServerPrepare = canHandleAsServerPreparedStatement(nativeSql);
		}
		
		if (this.useServerPreparedStmts && canServerPrepare) {
			if (this.getCachePreparedStatements()) {
				synchronized (this.serverSideStatementCache) {
					pStmt = (com.mysql.jdbc.ServerPreparedStatement)this.serverSideStatementCache.remove(sql);
					
					if (pStmt != null) {
						((com.mysql.jdbc.ServerPreparedStatement)pStmt).setClosed(false);
						pStmt.clearParameters();
					}

					if (pStmt == null) {
						try {
							pStmt = ServerPreparedStatement.getInstance(getLoadBalanceSafeProxy(), nativeSql,
									this.database, resultSetType, resultSetConcurrency);
							if (sql.length() < getPreparedStatementCacheSqlLimit()) {
								((com.mysql.jdbc.ServerPreparedStatement)pStmt).isCached = true;
							}
							
							pStmt.setResultSetType(resultSetType);
							pStmt.setResultSetConcurrency(resultSetConcurrency);
						} catch (SQLException sqlEx) {
							// Punt, if necessary
							if (getEmulateUnsupportedPstmts()) {
								pStmt = (PreparedStatement) clientPrepareStatement(nativeSql, resultSetType, resultSetConcurrency, false);
								
								if (sql.length() < getPreparedStatementCacheSqlLimit()) {
									this.serverSideStatementCheckCache.put(sql, Boolean.FALSE);
								}
							} else {
								throw sqlEx;
							}
						}
					}
				}
			} else {
				try {
					pStmt = ServerPreparedStatement.getInstance(getLoadBalanceSafeProxy(), nativeSql,
							this.database, resultSetType, resultSetConcurrency);
					
					pStmt.setResultSetType(resultSetType);
					pStmt.setResultSetConcurrency(resultSetConcurrency);
				} catch (SQLException sqlEx) {
					// Punt, if necessary
					if (getEmulateUnsupportedPstmts()) {
						pStmt = (PreparedStatement) clientPrepareStatement(nativeSql, resultSetType, resultSetConcurrency, false);
					} else {
						throw sqlEx;
					}
				}
			}
		} else {
			pStmt = (PreparedStatement) clientPrepareStatement(nativeSql, resultSetType, resultSetConcurrency, false);
		}
		
		return pStmt;
	}

	/**
	 * @see Connection#prepareStatement(String, int, int, int)
	 */
	public java.sql.PreparedStatement prepareStatement(String sql,
			int resultSetType, int resultSetConcurrency,
			int resultSetHoldability) throws SQLException {
		if (getPedantic()) {
			if (resultSetHoldability != java.sql.ResultSet.HOLD_CURSORS_OVER_COMMIT) {
				throw SQLError.createSQLException(
						"HOLD_CUSRORS_OVER_COMMIT is only supported holdability level",
						SQLError.SQL_STATE_ILLEGAL_ARGUMENT, getExceptionInterceptor());
			}
		}

		return prepareStatement(sql, resultSetType, resultSetConcurrency);
	}

	/**
	 * @see Connection#prepareStatement(String, int[])
	 */
	public java.sql.PreparedStatement prepareStatement(String sql,
			int[] autoGenKeyIndexes) throws SQLException {
		java.sql.PreparedStatement pStmt = prepareStatement(sql);

		((com.mysql.jdbc.PreparedStatement) pStmt)
				.setRetrieveGeneratedKeys((autoGenKeyIndexes != null)
						&& (autoGenKeyIndexes.length > 0));

		return pStmt;
	}

	/**
	 * @see Connection#prepareStatement(String, String[])
	 */
	public java.sql.PreparedStatement prepareStatement(String sql,
			String[] autoGenKeyColNames) throws SQLException {
		java.sql.PreparedStatement pStmt = prepareStatement(sql);

		((com.mysql.jdbc.PreparedStatement) pStmt)
				.setRetrieveGeneratedKeys((autoGenKeyColNames != null)
						&& (autoGenKeyColNames.length > 0));

		return pStmt;
	}

	/**
	 * Closes connection and frees resources.
	 * 
	 * @param calledExplicitly
	 *            is this being called from close()
	 * @param issueRollback
	 *            should a rollback() be issued?
	 * @throws SQLException
	 *             if an error occurs
	 */
	public void realClose(boolean calledExplicitly, boolean issueRollback,
			boolean skipLocalTeardown, Throwable reason) throws SQLException {
		SQLException sqlEx = null;

		if (this.isClosed()) {
			return;
		}
		
		this.forceClosedReason = reason;
		
		try {
			if (!skipLocalTeardown) {
				if (!getAutoCommit() && issueRollback) {
					try {
						rollback();
					} catch (SQLException ex) {
						sqlEx = ex;
					}
				}

				reportMetrics();

				if (getUseUsageAdvisor()) {
					if (!calledExplicitly) {
						String message = "Connection implicitly closed by Driver. You should call Connection.close() from your code to free resources more efficiently and avoid resource leaks.";

						this.eventSink.consumeEvent(new ProfilerEvent(
								ProfilerEvent.TYPE_WARN, "", //$NON-NLS-1$
								this.getCatalog(), this.getId(), -1, -1, System
										.currentTimeMillis(), 0, Constants.MILLIS_I18N,
										null,
								this.pointOfOrigin, message));
					}

					long connectionLifeTime = System.currentTimeMillis()
							- this.connectionCreationTimeMillis;

					if (connectionLifeTime < 500) {
						String message = "Connection lifetime of < .5 seconds. You might be un-necessarily creating short-lived connections and should investigate connection pooling to be more efficient.";

						this.eventSink.consumeEvent(new ProfilerEvent(
								ProfilerEvent.TYPE_WARN, "", //$NON-NLS-1$
								this.getCatalog(), this.getId(), -1, -1, System
										.currentTimeMillis(), 0, Constants.MILLIS_I18N,
										null,
								this.pointOfOrigin, message));
					}
				}

				try {
					closeAllOpenStatements();
				} catch (SQLException ex) {
					sqlEx = ex;
				}

				if (this.io != null) {
					try {
						this.io.quit();
					} catch (Exception e) {
						;
					}

				}
			} else {
				this.io.forceClose();
			}
			
	    	if (this.statementInterceptors != null) {
	    		for (int i = 0; i < this.statementInterceptors.size(); i++) {
	    			this.statementInterceptors.get(i).destroy();
	    		}
	    	}
	    	
	    	if (this.exceptionInterceptor != null) {
	    		this.exceptionInterceptor.destroy();
	    	}
		} finally {
			this.openStatements = null;
			this.io = null;
			this.statementInterceptors = null;
			this.exceptionInterceptor = null;
			ProfilerEventHandlerFactory.removeInstance(this);
			
			synchronized (this) {
				if (this.cancelTimer != null) {
					this.cancelTimer.cancel();
				}
			}
			
			this.isClosed = true;
		}

		if (sqlEx != null) {
			throw sqlEx;
		}

	}

	public synchronized void recachePreparedStatement(ServerPreparedStatement pstmt) throws SQLException {
		if (pstmt.isPoolable()) {
			synchronized (this.serverSideStatementCache) {
				this.serverSideStatementCache.put(pstmt.originalSql, pstmt);
			}
		}
	}

	/**
	 * DOCUMENT ME!
	 * 
	 * @param queryTimeMs
	 */
	public void registerQueryExecutionTime(long queryTimeMs) {
		if (queryTimeMs > this.longestQueryTimeMs) {
			this.longestQueryTimeMs = queryTimeMs;

			repartitionPerformanceHistogram();
		}

		addToPerformanceHistogram(queryTimeMs, 1);

		if (queryTimeMs < this.shortestQueryTimeMs) {
			this.shortestQueryTimeMs = (queryTimeMs == 0) ? 1 : queryTimeMs;
		}

		this.numberOfQueriesIssued++;

		this.totalQueryTimeMs += queryTimeMs;
	}

	/**
	 * Register a Statement instance as open.
	 * 
	 * @param stmt
	 *            the Statement instance to remove
	 */
	public void registerStatement(Statement stmt) {
		synchronized (this.openStatements) {
			this.openStatements.put(stmt, stmt);
		}
	}

	/**
	 * @see Connection#releaseSavepoint(Savepoint)
	 */
	public void releaseSavepoint(Savepoint arg0) throws SQLException {
		// this is a no-op
	}

	private void repartitionHistogram(int[] histCounts, long[] histBreakpoints,
			long currentLowerBound, long currentUpperBound) {

		if (oldHistCounts == null) {
			oldHistCounts = new int[histCounts.length];
			oldHistBreakpoints = new long[histBreakpoints.length];
		}

		System.arraycopy(histCounts, 0, oldHistCounts, 0, histCounts.length);
		
		System.arraycopy(histBreakpoints, 0, oldHistBreakpoints, 0,
				histBreakpoints.length);
	
		createInitialHistogram(histBreakpoints, currentLowerBound,
				currentUpperBound);

		for (int i = 0; i < HISTOGRAM_BUCKETS; i++) {
			addToHistogram(histCounts, histBreakpoints, oldHistBreakpoints[i],
					oldHistCounts[i], currentLowerBound, currentUpperBound);
		}
	}

	private void repartitionPerformanceHistogram() {
		checkAndCreatePerformanceHistogram();

		repartitionHistogram(this.perfMetricsHistCounts,
				this.perfMetricsHistBreakpoints,
				this.shortestQueryTimeMs == Long.MAX_VALUE ? 0
						: this.shortestQueryTimeMs, this.longestQueryTimeMs);
	}

	private void repartitionTablesAccessedHistogram() {
		checkAndCreateTablesAccessedHistogram();

		repartitionHistogram(this.numTablesMetricsHistCounts,
				this.numTablesMetricsHistBreakpoints,
				this.minimumNumberTablesAccessed == Long.MAX_VALUE ? 0
						: this.minimumNumberTablesAccessed,
				this.maximumNumberTablesAccessed);
	}

	private void reportMetrics() {
		if (getGatherPerformanceMetrics()) {
			StringBuffer logMessage = new StringBuffer(256);

			logMessage.append("** Performance Metrics Report **\n");
			logMessage.append("\nLongest reported query: "
					+ this.longestQueryTimeMs + " ms");
			logMessage.append("\nShortest reported query: "
					+ this.shortestQueryTimeMs + " ms");
			logMessage
					.append("\nAverage query execution time: "
							+ (this.totalQueryTimeMs / this.numberOfQueriesIssued)
							+ " ms");
			logMessage.append("\nNumber of statements executed: "
					+ this.numberOfQueriesIssued);
			logMessage.append("\nNumber of result sets created: "
					+ this.numberOfResultSetsCreated);
			logMessage.append("\nNumber of statements prepared: "
					+ this.numberOfPrepares);
			logMessage.append("\nNumber of prepared statement executions: "
					+ this.numberOfPreparedExecutes);

			if (this.perfMetricsHistBreakpoints != null) {
				logMessage.append("\n\n\tTiming Histogram:\n");
				int maxNumPoints = 20;
				int highestCount = Integer.MIN_VALUE;

				for (int i = 0; i < (HISTOGRAM_BUCKETS); i++) {
					if (this.perfMetricsHistCounts[i] > highestCount) {
						highestCount = this.perfMetricsHistCounts[i];
					}
				}

				if (highestCount == 0) {
					highestCount = 1; // avoid DIV/0
				}

				for (int i = 0; i < (HISTOGRAM_BUCKETS - 1); i++) {

					if (i == 0) {
						logMessage.append("\n\tless than "
								+ this.perfMetricsHistBreakpoints[i + 1]
								+ " ms: \t" + this.perfMetricsHistCounts[i]);
					} else {
						logMessage.append("\n\tbetween "
								+ this.perfMetricsHistBreakpoints[i] + " and "
								+ this.perfMetricsHistBreakpoints[i + 1]
								+ " ms: \t" + this.perfMetricsHistCounts[i]);
					}

					logMessage.append("\t");

					int numPointsToGraph = (int) (maxNumPoints * ((double) this.perfMetricsHistCounts[i] / (double) highestCount));

					for (int j = 0; j < numPointsToGraph; j++) {
						logMessage.append("*");
					}

					if (this.longestQueryTimeMs < this.perfMetricsHistCounts[i + 1]) {
						break;
					}
				}

				if (this.perfMetricsHistBreakpoints[HISTOGRAM_BUCKETS - 2] < this.longestQueryTimeMs) {
					logMessage.append("\n\tbetween ");
					logMessage
							.append(this.perfMetricsHistBreakpoints[HISTOGRAM_BUCKETS - 2]);
					logMessage.append(" and ");
					logMessage
							.append(this.perfMetricsHistBreakpoints[HISTOGRAM_BUCKETS - 1]);
					logMessage.append(" ms: \t");
					logMessage
							.append(this.perfMetricsHistCounts[HISTOGRAM_BUCKETS - 1]);
				}
			}

			if (this.numTablesMetricsHistBreakpoints != null) {
				logMessage.append("\n\n\tTable Join Histogram:\n");
				int maxNumPoints = 20;
				int highestCount = Integer.MIN_VALUE;

				for (int i = 0; i < (HISTOGRAM_BUCKETS); i++) {
					if (this.numTablesMetricsHistCounts[i] > highestCount) {
						highestCount = this.numTablesMetricsHistCounts[i];
					}
				}

				if (highestCount == 0) {
					highestCount = 1; // avoid DIV/0
				}

				for (int i = 0; i < (HISTOGRAM_BUCKETS - 1); i++) {

					if (i == 0) {
						logMessage.append("\n\t"
								+ this.numTablesMetricsHistBreakpoints[i + 1]
								+ " tables or less: \t\t"
								+ this.numTablesMetricsHistCounts[i]);
					} else {
						logMessage.append("\n\tbetween "
								+ this.numTablesMetricsHistBreakpoints[i]
								+ " and "
								+ this.numTablesMetricsHistBreakpoints[i + 1]
								+ " tables: \t"
								+ this.numTablesMetricsHistCounts[i]);
					}

					logMessage.append("\t");

					int numPointsToGraph = (int) (maxNumPoints * ((double) this.numTablesMetricsHistCounts[i] / (double) highestCount));

					for (int j = 0; j < numPointsToGraph; j++) {
						logMessage.append("*");
					}

					if (this.maximumNumberTablesAccessed < this.numTablesMetricsHistBreakpoints[i + 1]) {
						break;
					}
				}

				if (this.numTablesMetricsHistBreakpoints[HISTOGRAM_BUCKETS - 2] < this.maximumNumberTablesAccessed) {
					logMessage.append("\n\tbetween ");
					logMessage
							.append(this.numTablesMetricsHistBreakpoints[HISTOGRAM_BUCKETS - 2]);
					logMessage.append(" and ");
					logMessage
							.append(this.numTablesMetricsHistBreakpoints[HISTOGRAM_BUCKETS - 1]);
					logMessage.append(" tables: ");
					logMessage
							.append(this.numTablesMetricsHistCounts[HISTOGRAM_BUCKETS - 1]);
				}
			}

			this.log.logInfo(logMessage);

			this.metricsLastReportedMs = System.currentTimeMillis();
		}
	}

	/**
	 * Reports currently collected metrics if this feature is enabled and the
	 * timeout has passed.
	 */
	private void reportMetricsIfNeeded() {
		if (getGatherPerformanceMetrics()) {
			if ((System.currentTimeMillis() - this.metricsLastReportedMs) > getReportMetricsIntervalMillis()) {
				reportMetrics();
			}
		}
	}

	public void reportNumberOfTablesAccessed(int numTablesAccessed) {
		if (numTablesAccessed < this.minimumNumberTablesAccessed) {
			this.minimumNumberTablesAccessed = numTablesAccessed;
		}

		if (numTablesAccessed > this.maximumNumberTablesAccessed) {
			this.maximumNumberTablesAccessed = numTablesAccessed;

			repartitionTablesAccessedHistogram();
		}

		addToTablesAccessedHistogram(numTablesAccessed, 1);
	}

	/**
	 * Resets the server-side state of this connection. Doesn't work for MySQL
	 * versions older than 4.0.6 or if isParanoid() is set (it will become a
	 * no-op in these cases). Usually only used from connection pooling code.
	 * 
	 * @throws SQLException
	 *             if the operation fails while resetting server state.
	 */
	public void resetServerState() throws SQLException {
		if (!getParanoid()
				&& ((this.io != null) && versionMeetsMinimum(4, 0, 6))) {
			changeUser(this.user, this.password);
		}
	}

	/**
	 * The method rollback() drops all changes made since the previous
	 * commit/rollback and releases any database locks currently held by the
	 * Connection.
	 * 
	 * @exception SQLException
	 *                if a database access error occurs
	 * @see commit
	 */
	public synchronized void rollback() throws SQLException {
		checkClosed();

		try {
			if (this.connectionLifecycleInterceptors != null) {
				IterateBlock iter = new IterateBlock(this.connectionLifecycleInterceptors.iterator()) {

					void forEach(Object each) throws SQLException {
						if (!((ConnectionLifecycleInterceptor)each).rollback()) {
							this.stopIterating = true;
						}
					}
				};
				
				iter.doForAll();
				
				if (!iter.fullIteration()) {
					return;
				}
			}
			// no-op if _relaxAutoCommit == true
			if (this.autoCommit && !getRelaxAutoCommit()) {
				throw SQLError.createSQLException(
						"Can't call rollback when autocommit=true",
						SQLError.SQL_STATE_CONNECTION_NOT_OPEN, getExceptionInterceptor());
			} else if (this.transactionsSupported) {
				try {
					rollbackNoChecks();
				} catch (SQLException sqlEx) {
					// We ignore non-transactional tables if told to do so
					if (getIgnoreNonTxTables()
							&& (sqlEx.getErrorCode() == SQLError.ER_WARNING_NOT_COMPLETE_ROLLBACK)) {
						return;
					}
					throw sqlEx;

				}
			}
		} catch (SQLException sqlException) {
			if (SQLError.SQL_STATE_COMMUNICATION_LINK_FAILURE
					.equals(sqlException.getSQLState())) {
				throw SQLError.createSQLException(
						"Communications link failure during rollback(). Transaction resolution unknown.",
						SQLError.SQL_STATE_TRANSACTION_RESOLUTION_UNKNOWN, getExceptionInterceptor());
			}

			throw sqlException;
		} finally {
			this.needsPing = this.getReconnectAtTxEnd();
		}
	}

	/**
	 * @see Connection#rollback(Savepoint)
	 */
	public synchronized void rollback(final Savepoint savepoint) throws SQLException {

		if (versionMeetsMinimum(4, 0, 14) || versionMeetsMinimum(4, 1, 1)) {
			checkClosed();
	
			try {
				if (this.connectionLifecycleInterceptors != null) {
					IterateBlock iter = new IterateBlock(this.connectionLifecycleInterceptors.iterator()) {

						void forEach(Object each) throws SQLException {
							if (!((ConnectionLifecycleInterceptor)each).rollback(savepoint)) {
								this.stopIterating = true;
							}
						}
					};
					
					iter.doForAll();
					
					if (!iter.fullIteration()) {
						return;
					}
				}
				
				StringBuffer rollbackQuery = new StringBuffer(
						"ROLLBACK TO SAVEPOINT ");
				rollbackQuery.append('`');
				rollbackQuery.append(savepoint.getSavepointName());
				rollbackQuery.append('`');

				java.sql.Statement stmt = null;

				try {
					stmt = getMetadataSafeStatement();

					stmt.executeUpdate(rollbackQuery.toString());
				} catch (SQLException sqlEx) {
					int errno = sqlEx.getErrorCode();

					if (errno == 1181) {
						String msg = sqlEx.getMessage();

						if (msg != null) {
							int indexOfError153 = msg.indexOf("153");

							if (indexOfError153 != -1) {
								throw SQLError.createSQLException("Savepoint '"
										+ savepoint.getSavepointName()
										+ "' does not exist",
										SQLError.SQL_STATE_ILLEGAL_ARGUMENT,
										errno, getExceptionInterceptor());
							}
						}
					}

					// We ignore non-transactional tables if told to do so
					if (getIgnoreNonTxTables()
							&& (sqlEx.getErrorCode() != SQLError.ER_WARNING_NOT_COMPLETE_ROLLBACK)) {
						throw sqlEx;
					}

					if (SQLError.SQL_STATE_COMMUNICATION_LINK_FAILURE
							.equals(sqlEx.getSQLState())) {
						throw SQLError.createSQLException(
								"Communications link failure during rollback(). Transaction resolution unknown.",
								SQLError.SQL_STATE_TRANSACTION_RESOLUTION_UNKNOWN, getExceptionInterceptor());
					}

					throw sqlEx;
				} finally {
					closeStatement(stmt);
				}
			} finally {
				this.needsPing = this.getReconnectAtTxEnd();
			}
		} else {
			throw SQLError.notImplemented();
		}
	}

	private void rollbackNoChecks() throws SQLException {
		if (getUseLocalTransactionState() && versionMeetsMinimum(5, 0, 0)) {
			if (!this.io.inTransactionOnServer()) {
				return; // effectively a no-op
			}
		}
		
		execSQL(null, "rollback", -1, null,
				DEFAULT_RESULT_SET_TYPE,
				DEFAULT_RESULT_SET_CONCURRENCY, false,
				this.database, null, false);
	}

	/**
	 * @see java.sql.Connection#prepareStatement(String)
	 */
	public java.sql.PreparedStatement serverPrepareStatement(String sql)
		throws SQLException {

		String nativeSql = getProcessEscapeCodesForPrepStmts() ? nativeSQL(sql): sql;

		return ServerPreparedStatement.getInstance(getLoadBalanceSafeProxy(), nativeSql, this.getCatalog(),
				DEFAULT_RESULT_SET_TYPE,
				DEFAULT_RESULT_SET_CONCURRENCY);
	}

	/**
	 * @see java.sql.Connection#prepareStatement(String, int)
	 */
	public java.sql.PreparedStatement serverPrepareStatement(String sql,
			int autoGenKeyIndex) throws SQLException {
		String nativeSql = getProcessEscapeCodesForPrepStmts() ? nativeSQL(sql): sql;

		PreparedStatement pStmt = ServerPreparedStatement.getInstance(getLoadBalanceSafeProxy(), nativeSql, this.getCatalog(),
				DEFAULT_RESULT_SET_TYPE,
				DEFAULT_RESULT_SET_CONCURRENCY);
		
		pStmt.setRetrieveGeneratedKeys(
				autoGenKeyIndex == java.sql.Statement.RETURN_GENERATED_KEYS);

		return pStmt;
	}
	
	/**
	 * @see java.sql.Connection#prepareStatement(String, int, int)
	 */
	public java.sql.PreparedStatement serverPrepareStatement(String sql,
			int resultSetType, int resultSetConcurrency) throws SQLException {
		String nativeSql = getProcessEscapeCodesForPrepStmts() ? nativeSQL(sql): sql;

		return ServerPreparedStatement.getInstance(getLoadBalanceSafeProxy(), nativeSql, this.getCatalog(),
				resultSetType,
				resultSetConcurrency);
	}
	
	/**
	 * @see java.sql.Connection#prepareStatement(String, int, int, int)
	 */
	public java.sql.PreparedStatement serverPrepareStatement(String sql,
			int resultSetType, int resultSetConcurrency,
			int resultSetHoldability) throws SQLException {
		if (getPedantic()) {
			if (resultSetHoldability != java.sql.ResultSet.HOLD_CURSORS_OVER_COMMIT) {
				throw SQLError.createSQLException(
						"HOLD_CUSRORS_OVER_COMMIT is only supported holdability level",
						SQLError.SQL_STATE_ILLEGAL_ARGUMENT, getExceptionInterceptor());
			}
		}

		return serverPrepareStatement(sql, resultSetType, resultSetConcurrency);
	}
	
	/**
	 * @see java.sql.Connection#prepareStatement(String, int[])
	 */
	public java.sql.PreparedStatement serverPrepareStatement(String sql,
			int[] autoGenKeyIndexes) throws SQLException {
		
		PreparedStatement pStmt = (PreparedStatement) serverPrepareStatement(sql);
		
		pStmt
				.setRetrieveGeneratedKeys((autoGenKeyIndexes != null)
						&& (autoGenKeyIndexes.length > 0));

		return pStmt;
	}

	/**
	 * @see java.sql.Connection#prepareStatement(String, String[])
	 */
	public java.sql.PreparedStatement serverPrepareStatement(String sql,
			String[] autoGenKeyColNames) throws SQLException {
		PreparedStatement pStmt = (PreparedStatement) serverPrepareStatement(sql);

		pStmt
				.setRetrieveGeneratedKeys((autoGenKeyColNames != null)
						&& (autoGenKeyColNames.length > 0));

		return pStmt;
	}
	
	public boolean serverSupportsConvertFn() throws SQLException {
		return versionMeetsMinimum(4, 0, 2);
	}

	/**
	 * If a connection is in auto-commit mode, than all its SQL statements will
	 * be executed and committed as individual transactions. Otherwise, its SQL
	 * statements are grouped into transactions that are terminated by either
	 * commit() or rollback(). By default, new connections are in auto- commit
	 * mode. The commit occurs when the statement completes or the next execute
	 * occurs, whichever comes first. In the case of statements returning a
	 * ResultSet, the statement completes when the last row of the ResultSet has
	 * been retrieved or the ResultSet has been closed. In advanced cases, a
	 * single statement may return multiple results as well as output parameter
	 * values. Here the commit occurs when all results and output param values
	 * have been retrieved.
	 * <p>
	 * <b>Note:</b> MySQL does not support transactions, so this method is a
	 * no-op.
	 * </p>
	 * 
	 * @param autoCommitFlag -
	 *            true enables auto-commit; false disables it
	 * @exception SQLException
	 *                if a database access error occurs
	 */
	public synchronized void setAutoCommit(final boolean autoCommitFlag) throws SQLException {
		checkClosed();
		
		if (this.connectionLifecycleInterceptors != null) {
			IterateBlock iter = new IterateBlock(this.connectionLifecycleInterceptors.iterator()) {

				void forEach(Object each) throws SQLException {
					if (!((ConnectionLifecycleInterceptor)each).setAutoCommit(autoCommitFlag)) {
						this.stopIterating = true;
					}
				}
			};
			
			iter.doForAll();
			
			if (!iter.fullIteration()) {
				return;
			}
		}

		if (getAutoReconnectForPools()) {
			setHighAvailability(true);
		}

		try {
			if (this.transactionsSupported) {

				boolean needsSetOnServer = true;

				if (this.getUseLocalSessionState()
						&& this.autoCommit == autoCommitFlag) {
					needsSetOnServer = false;
				} else if (!this.getHighAvailability()) {
					needsSetOnServer = this.getIO()
							.isSetNeededForAutoCommitMode(autoCommitFlag);
				}

				// this internal value must be set first as failover depends on
				// it
				// being set to true to fail over (which is done by most
				// app servers and connection pools at the end of
				// a transaction), and the driver issues an implicit set
				// based on this value when it (re)-connects to a server
				// so the value holds across connections
				this.autoCommit = autoCommitFlag;

				if (needsSetOnServer) {
					execSQL(null, autoCommitFlag ? "SET autocommit=1"
							: "SET autocommit=0", -1, null,
							DEFAULT_RESULT_SET_TYPE,
							DEFAULT_RESULT_SET_CONCURRENCY, false,
							this.database, null, false);
				}

			} else {
				if ((autoCommitFlag == false) && !getRelaxAutoCommit()) {
					throw SQLError.createSQLException("MySQL Versions Older than 3.23.15 "
							+ "do not support transactions",
							SQLError.SQL_STATE_CONNECTION_NOT_OPEN, getExceptionInterceptor());
				}

				this.autoCommit = autoCommitFlag;
			}
		} finally {
			if (this.getAutoReconnectForPools()) {
				setHighAvailability(false);
			}
		}
		
		return;
	}

	/**
	 * A sub-space of this Connection's database may be selected by setting a
	 * catalog name. If the driver does not support catalogs, it will silently
	 * ignore this request
	 * <p>
	 * <b>Note:</b> MySQL's notion of catalogs are individual databases.
	 * </p>
	 * 
	 * @param catalog
	 *            the database for this connection to use
	 * @throws SQLException
	 *             if a database access error occurs
	 */
	public synchronized void setCatalog(final String catalog) throws SQLException {
		checkClosed();

		if (catalog == null) {
			throw SQLError.createSQLException("Catalog can not be null",
					SQLError.SQL_STATE_ILLEGAL_ARGUMENT, getExceptionInterceptor());
		}
		
		if (this.connectionLifecycleInterceptors != null) {
			IterateBlock iter = new IterateBlock(this.connectionLifecycleInterceptors.iterator()) {

				void forEach(Object each) throws SQLException {
					if (!((ConnectionLifecycleInterceptor)each).setCatalog(catalog)) {
						this.stopIterating = true;
					}
				}
			};
			
			iter.doForAll();
			
			if (!iter.fullIteration()) {
				return;
			}
		}
		
		if (getUseLocalSessionState()) {
			if (this.lowerCaseTableNames) {
				if (this.database.equalsIgnoreCase(catalog)) {
					return;
				}
			} else {
				if (this.database.equals(catalog)) {
					return;
				}
			}
		}
		
		String quotedId = this.dbmd.getIdentifierQuoteString();

		if ((quotedId == null) || quotedId.equals(" ")) {
			quotedId = "";
		}

		StringBuffer query = new StringBuffer("USE ");
		query.append(quotedId);
		query.append(catalog);
		query.append(quotedId);

		execSQL(null, query.toString(), -1, null,
				DEFAULT_RESULT_SET_TYPE,
				DEFAULT_RESULT_SET_CONCURRENCY, false,
				this.database, null, false);
		
		this.database = catalog;
	}

	/**
	 * @param failedOver
	 *            The failedOver to set.
	 */
	public synchronized void setFailedOver(boolean flag) {
		// handled higher up
	}

	/**
	 * @see Connection#setHoldability(int)
	 */
	public void setHoldability(int arg0) throws SQLException {
		// do nothing
	}

	public void setInGlobalTx(boolean flag) {
		this.isInGlobalTx = flag;
	}

	// exposed for testing
	/**
	 * @param preferSlaveDuringFailover
	 *            The preferSlaveDuringFailover to set.
	 */
	public void setPreferSlaveDuringFailover(boolean flag) {
		// no-op, handled further up in the wrapper
	}

	public void setReadInfoMsgEnabled(boolean flag) {
		this.readInfoMsg = flag;
	}

	/**
	 * You can put a connection in read-only mode as a hint to enable database
	 * optimizations <B>Note:</B> setReadOnly cannot be called while in the
	 * middle of a transaction
	 * 
	 * @param readOnlyFlag -
	 *            true enables read-only mode; false disables it
	 * @exception SQLException
	 *                if a database access error occurs
	 */
	public void setReadOnly(boolean readOnlyFlag) throws SQLException {
		checkClosed();

		setReadOnlyInternal(readOnlyFlag);
	}
	
	public void setReadOnlyInternal(boolean readOnlyFlag) throws SQLException {
		this.readOnly = readOnlyFlag;
	}
	
	/**
	 * @see Connection#setSavepoint()
	 */
	public java.sql.Savepoint setSavepoint() throws SQLException {
		MysqlSavepoint savepoint = new MysqlSavepoint(getExceptionInterceptor());

		setSavepoint(savepoint);

		return savepoint;
	}

	private synchronized void setSavepoint(MysqlSavepoint savepoint) throws SQLException {

		if (versionMeetsMinimum(4, 0, 14) || versionMeetsMinimum(4, 1, 1)) {
			checkClosed();

			StringBuffer savePointQuery = new StringBuffer("SAVEPOINT ");
			savePointQuery.append('`');
			savePointQuery.append(savepoint.getSavepointName());
			savePointQuery.append('`');

			java.sql.Statement stmt = null;

			try {
				stmt = getMetadataSafeStatement();

				stmt.executeUpdate(savePointQuery.toString());
			} finally {
				closeStatement(stmt);
			}
		} else {
			throw SQLError.notImplemented();
		}
	}
	
	/**
	 * @see Connection#setSavepoint(String)
	 */
	public synchronized java.sql.Savepoint setSavepoint(String name) throws SQLException {
		MysqlSavepoint savepoint = new MysqlSavepoint(name, getExceptionInterceptor());

		setSavepoint(savepoint);

		return savepoint;
	}
	
	/**
	 * 
	 */
	private void setSessionVariables() throws SQLException {
		if (this.versionMeetsMinimum(4, 0, 0) && getSessionVariables() != null) {
			List<String> variablesToSet = StringUtils.split(getSessionVariables(), ",", "\"'", "\"'",
					false);

			int numVariablesToSet = variablesToSet.size();

			java.sql.Statement stmt = null;

			try {
				stmt = getMetadataSafeStatement();

				for (int i = 0; i < numVariablesToSet; i++) {
					String variableValuePair = variablesToSet.get(i);

					if (variableValuePair.startsWith("@")) {
						stmt.executeUpdate("SET " + variableValuePair);
					} else {
						stmt.executeUpdate("SET SESSION " + variableValuePair);
					}
				}
			} finally {
				if (stmt != null) {
					stmt.close();
				}
			}
		}

	}
	
	/**
	 * DOCUMENT ME!
	 * 
	 * @param level
	 *            DOCUMENT ME!
	 * @throws SQLException
	 *             DOCUMENT ME!
	 */
	public synchronized void setTransactionIsolation(int level) throws SQLException {
		checkClosed();

		if (this.hasIsolationLevels) {
			String sql = null;

			boolean shouldSendSet = false;

			if (getAlwaysSendSetIsolation()) {
				shouldSendSet = true;
			} else {
				if (level != this.isolationLevel) {
					shouldSendSet = true;
				}
			}

			if (getUseLocalSessionState()) {
				shouldSendSet = this.isolationLevel != level;
			}

			if (shouldSendSet) {
				switch (level) {
				case java.sql.Connection.TRANSACTION_NONE:
					throw SQLError.createSQLException("Transaction isolation level "
							+ "NONE not supported by MySQL", getExceptionInterceptor());

				case java.sql.Connection.TRANSACTION_READ_COMMITTED:
					sql = "SET SESSION TRANSACTION ISOLATION LEVEL READ COMMITTED";

					break;

				case java.sql.Connection.TRANSACTION_READ_UNCOMMITTED:
					sql = "SET SESSION TRANSACTION ISOLATION LEVEL READ UNCOMMITTED";

					break;

				case java.sql.Connection.TRANSACTION_REPEATABLE_READ:
					sql = "SET SESSION TRANSACTION ISOLATION LEVEL REPEATABLE READ";

					break;

				case java.sql.Connection.TRANSACTION_SERIALIZABLE:
					sql = "SET SESSION TRANSACTION ISOLATION LEVEL SERIALIZABLE";

					break;

				default:
					throw SQLError.createSQLException("Unsupported transaction "
							+ "isolation level '" + level + "'",
							SQLError.SQL_STATE_DRIVER_NOT_CAPABLE, getExceptionInterceptor());
				}

				execSQL(null, sql, -1, null,
						DEFAULT_RESULT_SET_TYPE,
						DEFAULT_RESULT_SET_CONCURRENCY,false,
						this.database, null, false);

				this.isolationLevel = level;
			}
		} else {
			throw SQLError.createSQLException("Transaction Isolation Levels are "
					+ "not supported on MySQL versions older than 3.23.36.",
					SQLError.SQL_STATE_DRIVER_NOT_CAPABLE, getExceptionInterceptor());
		}
	}
	
	/**
	 * JDBC 2.0 Install a type-map object as the default type-map for this
	 * connection
	 * 
	 * @param map
	 *            the type mapping
	 * @throws SQLException
	 *             if a database error occurs.
	 */
	public synchronized void setTypeMap(java.util.Map map) throws SQLException {
		this.typeMap = map;
	}
	
	private void setupServerForTruncationChecks() throws SQLException {
		if (getJdbcCompliantTruncation()) {
			if (versionMeetsMinimum(5, 0, 2)) {
				String currentSqlMode = 
					this.serverVariables.get("sql_mode");
				
				boolean strictTransTablesIsSet = StringUtils.indexOfIgnoreCase(currentSqlMode, "STRICT_TRANS_TABLES") != -1;
				
				if (currentSqlMode == null ||
						currentSqlMode.length() == 0 || !strictTransTablesIsSet) {
					StringBuffer commandBuf = new StringBuffer("SET sql_mode='");
					
					if (currentSqlMode != null && currentSqlMode.length() > 0) {
						commandBuf.append(currentSqlMode);
						commandBuf.append(",");
					}
					
					commandBuf.append("STRICT_TRANS_TABLES'");
					
					execSQL(null,  commandBuf.toString(), -1, null,
							DEFAULT_RESULT_SET_TYPE,
							DEFAULT_RESULT_SET_CONCURRENCY, false,
							this.database, null, false);
					
					setJdbcCompliantTruncation(false); // server's handling this for us now
				} else if (strictTransTablesIsSet) {
					// We didn't set it, but someone did, so we piggy back on it
					setJdbcCompliantTruncation(false); // server's handling this for us now
				}
				
			}
		}
	}
	
	
	/**
	 * Used by MiniAdmin to shutdown a MySQL server
	 * 
	 * @throws SQLException
	 *             if the command can not be issued.
	 */
	public void shutdownServer() throws SQLException {
		try {
			this.io.sendCommand(MysqlDefs.SHUTDOWN, null, null, false, null, 0);
		} catch (Exception ex) {
			SQLException sqlEx = SQLError.createSQLException(
					Messages.getString("Connection.UnhandledExceptionDuringShutdown"),
					SQLError.SQL_STATE_GENERAL_ERROR, getExceptionInterceptor());
			
			sqlEx.initCause(ex);
			
			throw sqlEx;
		}
	}

	/**
	 * DOCUMENT ME!
	 * 
	 * @return DOCUMENT ME!
	 */
	public boolean supportsIsolationLevel() {
		return this.hasIsolationLevels;
	}
	
	/**
	 * DOCUMENT ME!
	 * 
	 * @return DOCUMENT ME!
	 */
	public boolean supportsQuotedIdentifiers() {
		return this.hasQuotedIdentifiers;
	}

	/**
	 * DOCUMENT ME!
	 * 
	 * @return DOCUMENT ME!
	 */
	public boolean supportsTransactions() {
		return this.transactionsSupported;
	}

	/**
	 * Remove the given statement from the list of open statements
	 * 
	 * @param stmt
	 *            the Statement instance to remove
	 */
	public void unregisterStatement(Statement stmt) {
		if (this.openStatements != null) {
			synchronized (this.openStatements) {
				this.openStatements.remove(stmt);
			}
		}
	}

	/**
	 * Called by statements on their .close() to let the connection know when it
	 * is safe to set the connection back to 'default' row limits.
	 * 
	 * @param stmt
	 *            the statement releasing it's max-rows requirement
	 * @throws SQLException
	 *             if a database error occurs issuing the statement that sets
	 *             the limit default.
	 */
	public synchronized void unsetMaxRows(Statement stmt) throws SQLException {
		if (this.statementsUsingMaxRows != null) {
			Object found = this.statementsUsingMaxRows.remove(stmt);

			if ((found != null)
					&& (this.statementsUsingMaxRows.size() == 0)) {
				execSQL(null, "SET SQL_SELECT_LIMIT=DEFAULT", -1,
						null, DEFAULT_RESULT_SET_TYPE,
						DEFAULT_RESULT_SET_CONCURRENCY, false, 
						this.database, null, false);

				this.maxRowsChanged = false;
			}
		}
	}
	
	public synchronized boolean useAnsiQuotedIdentifiers() {
		return this.useAnsiQuotes;
	}
	
	/**
	 * Has maxRows() been set?
	 * 
	 * @return DOCUMENT ME!
	 */
	public synchronized boolean useMaxRows() {
		return this.maxRowsChanged;
	}
	
	public boolean versionMeetsMinimum(int major, int minor, int subminor)
			throws SQLException {
		checkClosed();

		return this.io.versionMeetsMinimum(major, minor, subminor);
	}

	/**
	 * Returns cached metadata (or null if not cached) for the given query,
	 * which must match _exactly_.	 
	 *  
	 * This method is synchronized by the caller on getMutex(), so if
	 * calling this method from internal code in the driver, make sure it's
	 * synchronized on the mutex that guards communication with the server.
	 * 
	 * @param sql
	 *            the query that is the key to the cache
	 * 
	 * @return metadata cached for the given SQL, or none if it doesn't
	 *                  exist.
	 */
	public CachedResultSetMetaData getCachedMetaData(String sql) {
		if (this.resultSetMetadataCache != null) {
			synchronized (this.resultSetMetadataCache) {
				return (CachedResultSetMetaData) this.resultSetMetadataCache
						.get(sql);
			}
		}

		return null; // no cache exists
	}

	/**
	 * Caches CachedResultSetMetaData that has been placed in the cache using
	 * the given SQL as a key.
	 * 
	 * This method is synchronized by the caller on getMutex(), so if
	 * calling this method from internal code in the driver, make sure it's
	 * synchronized on the mutex that guards communication with the server.
	 * 
	 * @param sql the query that the metadata pertains too.
	 * @param cachedMetaData metadata (if it exists) to populate the cache.
	 * @param resultSet the result set to retreive metadata from, or apply to.
	 *
	 * @throws SQLException
	 */
	public void initializeResultsMetadataFromCache(String sql,
			CachedResultSetMetaData cachedMetaData, ResultSetInternalMethods resultSet)
			throws SQLException {

		if (cachedMetaData == null) {
			
			// read from results
			cachedMetaData = new CachedResultSetMetaData();

			// assume that users will use named-based
			// lookups
			resultSet.buildIndexMapping();
			resultSet.initializeWithMetadata();

			if (resultSet instanceof UpdatableResultSet) {
				((UpdatableResultSet)resultSet).checkUpdatability();
			}

			resultSet.populateCachedMetaData(cachedMetaData);

			this.resultSetMetadataCache.put(sql, cachedMetaData);
		} else {
			resultSet.initializeFromCachedMetaData(cachedMetaData);
			resultSet.initializeWithMetadata();
			
			if (resultSet instanceof UpdatableResultSet) {
				((UpdatableResultSet)resultSet).checkUpdatability();
			}
		}
	}
	
	/**
	 * Returns the comment that will be prepended to all statements
	 * sent to the server.
	 * 
	 * @return the comment that will be prepended to all statements
	 * sent to the server.
	 */
	public String getStatementComment() {
		return this.statementComment;
	}

	/**
	 * Sets the comment that will be prepended to all statements
	 * sent to the server. Do not use slash-star or star-slash tokens 
	 * in the comment as these will be added by the driver itself.
	 * 
	 * @param comment  the comment that will be prepended to all statements
	 * sent to the server.
	 */
	public void setStatementComment(String comment) {
		this.statementComment = comment;
	}
	
	public synchronized void reportQueryTime(long millisOrNanos) {
		this.queryTimeCount++;
		this.queryTimeSum += millisOrNanos;
		this.queryTimeSumSquares += (millisOrNanos * millisOrNanos);
		this.queryTimeMean = ((this.queryTimeMean * (this.queryTimeCount - 1)) + millisOrNanos)
				/ this.queryTimeCount;
	}
	
	public synchronized boolean isAbonormallyLongQuery(long millisOrNanos) {
		if (this.queryTimeCount < 15) {
			return false; // need a minimum amount for this to make sense
		}
		
		double stddev = Math.sqrt((this.queryTimeSumSquares - ((this.queryTimeSum*this.queryTimeSum) / this.queryTimeCount)) / (this.queryTimeCount - 1));
		
		return millisOrNanos > (this.queryTimeMean + 5 * stddev);
	}

	public void initializeExtension(Extension ex) throws SQLException {
		ex.init(this, this.props);
	}
	
	public synchronized void transactionBegun() throws SQLException {
		if (this.connectionLifecycleInterceptors != null) {
			IterateBlock iter = new IterateBlock(this.connectionLifecycleInterceptors.iterator()) {

				void forEach(Object each) throws SQLException {
					((ConnectionLifecycleInterceptor)each).transactionBegun();
				}
			};
			
			iter.doForAll();
		}
	}
	
	public synchronized void transactionCompleted() throws SQLException {
		if (this.connectionLifecycleInterceptors != null) {
			IterateBlock iter = new IterateBlock(this.connectionLifecycleInterceptors.iterator()) {

				void forEach(Object each) throws SQLException {
					((ConnectionLifecycleInterceptor)each).transactionCompleted();
				}
			};
			
			iter.doForAll();
		}
	}
	
	public boolean storesLowerCaseTableName() {
		return storesLowerCaseTableName;
	}
	
	private ExceptionInterceptor exceptionInterceptor;
	
	public ExceptionInterceptor getExceptionInterceptor() {
		return this.exceptionInterceptor;
	}
	
	public boolean getRequiresEscapingEncoder() {
		return requiresEscapingEncoder;
	}
	
	public synchronized boolean isServerLocal() throws SQLException {
		SocketFactory factory = getIO().socketFactory;
		
		if (factory instanceof SocketMetadata) {
			return ((SocketMetadata)factory).isLocallyConnected(this);
		} 
		getLog().logWarn(Messages.getString("Connection.NoMetadataOnSocketFactory"));
		return false;
	}
}
